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Department Of Materials Science & Engineering.
Materials @ Sheffield 2012.
Departm
ent of Materials S
cience & Engineering M
aterials @ S
heffield 2012
Materials Science and EngineeringThe University of SheffieldSir Robert Hadfield BuildingMappin StreetSheffield S1 3JDUnited Kingdom
Tel: +44 (0)114 222 5941Fax: +44 (0)114 222 5943
www.shef.ac.uk/materials
Every effort has been made to ensure the accuracy of the information given in this publication. However, the university reserves the right to make changes. D
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Materials@Sheffield 2012
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Content
Contents
Page No
1 Head of Department Introduction 5
2 Staff in the Department of Materials Science and Engineering 7
3 Industrial Liaison Committee 11
4 Academic Staff Profiles 13
5 Research Highlights 2011 21
5.1. Biomaterials and Tissue Engineering 22
5.2. Functional Materials and Devices 28
5.3. Nuclear Energy 34
5.4. Advanced Structural Materials 40
5.5 Multiscale Materials Modelling 48
5.6 Nanomaterials and Nanoengineering 52
6 Publications, 2011 56
7 PhD Awards, 2011 66
8 Current Research Sponsors 67
9 Grants and Contracts Awarded 2011 70
10 Personal Highlights 2011 71
11 Retired Academic Staff Profiles 80
12 Appendix: Annual Report 2012 (separate report)
Production Team:Wendy Dutton and Vanessa Dalton
Editor:Professor W M Rainforth
Department of Materials Science and EngineeringThe University of SheffieldSir Robert Hadfield BuildingMappin StreetSheffield S1 3JDUnited Kingdom
Tel: +44 (0)114 222 5941Fax: +44 (0)114 222 5943
www.shef.ac.uk/materials
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Introduction1
The Department of Materials Science and Engineering at the University of Sheffield is one of the largest departments in the UK and internationally renowned for its research and teaching. The Department has its origins in the last 19th century, and indeed was one of the founding departments of the University (which received its Royal Charter in 1905). In the early days key subjects such as metallurgy underpinned the huge industrial strength of Sheffield, particularly in the world dominant steel industry. Today, the Department has internationally recognised research is a wide range of topics, including biomaterials, tissue engineering, functional ceramics, magnetics, surface engineering, tribology, glass, nuclear waste immobilisation, cements and geopolymers, multiscale materials modelling, thermomechanical processing of metals, additive layer manufacturing, manufacturing, high temperature materials, energy materials, polymer composites, functional polymers, nanocharacterisation, nanomaterials and nanorobotics. We group ourselves into 6 broad themes, namely, Biomaterials and Tissue Engineering; Functional Materials and Devices; Nuclear Engineering; Multiscale Materials Modelling; Nanomaterials and Nanoengineering; Advanced Structural Materials. Research highlights from each of these themes forms the largest part of this report.
The subject of Materials is ubiquitous and underpins technology that enters everyone’s daily lives, for example, from transport to mobile devices to healthcare to the energy sector. The vision of the Materials Science and Engineering team at Sheffield is to produce world-class research that impacts directly on society and industrial processing. Our research is often guided by industrial need, which is shown by the 120 companies and Government agencies who sponsor our work. Equally, we undertake fundamental research, which frequently impacts in later years. The impact of our research is widely publicised and there have been many examples over the last year. For example, Prof Sheila MacNeil has developed a wound dressing that glows to indicate an infection through a gel containing molecules that bind to bacteria and activate a fluorescent dye. Doctors can then make the best decision about how to treat the wound. As well as shining a spotlight on bacteria, the gel can rid a wound of up to 80% of surface bugs in around three hours. This work was highlighted in all of the mainstream national press. Dr Fred Claeyssens was highlighted by the BBC for his work on a “miniature honeycomb” - or scaffold - that could one day be used to encourage damaged nerves to grow and recover. The scaffold can channel clusters of nerves through its honeycomb of holes, eventually healing a severed nerve, which could one day make a huge difference to patients suffering severe nerve damage. Our work in nuclear waste immobilisation is known around the globe. Following the Tohoku earthquake and tsunami on 11 March 2011, Prof Neil Hyatt gave over 20 media interviews to national newspapers and television channels in relation to the Fukushima Dai-ichi incident, including live appearances on BBC News 24. He was also a key note speaker and panellist at the special “The Future of Nuclear Power Post Fukushima” session of the Green Party National
Conference, Sheffield, 11 September 2011. Antenna (i.e. aerials) are ubiquitous in devices we use in everyday life from radios, televisions, cell phones, satellites, bluetooth devices, wireless computing networks and so on. The efficiency of the antenna is critical, as anyone trying to use a cell phone with a weak signal will know. Prof Ian Reaney has developed new materials for the core of antennas that boost their efficiency. By introducing a radically different manufacturing route, replacing the traditional solid state synthesis by a route where a glass is formed, followed by heat treatment to give controlled crystallisation to form a glass ceramic, antennae with higher efficiency have been produced and the knowledge transferred to industry. Following the announcement of the £5m ERDF grant to Prof Mark Rainforth and Prof Iain Todd to fund the Mercury Centre for Innovative Materials and Manufacturing, the Centre was formally opened in 2011. Benefiting from a long overdue £300k refurbishment of the Quarrell Laboratory, the Centre focuses on the demand for more sophisticated products made with radically improved resource-efficiency. Powder-based manufacturing encompasses a range of new processes such as high-speed sintering, additive-layer, and entrained-jet manufacturing. Equipment at the centre includes Additive Layer Manufacture, Deep Repair, Aerosol Jet Deposition, Spark Plasma Sintering, Metal Injection Moulding and Advanced Materials Characterisation. These new manufacturing technologies have attracted substantial interest from industry, from SMEs to large organisations such as Rolls-Royce.
We continue to be a leading force in grant capture. Of the many grants won, it was particularly pleasing to see Dr Tom Hayward win a prestigious EPSRC Career Acceleration fellowship. Tom is currently working with Dr Dan Allwood developing novel techniques for manipulating ultra-cold paramagnetic atoms using the magnetic fringing fields created by ferromagnetic nanostructures. The award is entitled “Magnetism You Can Rely On: Understanding Stochastic Behaviour in Nanomagnetic devices” and has a total value of £700k. Profs Sheila MacNeil and John Haycock along with Prof R Smallwood, have been awarded £500k for “P&G: coupled in vitro and computational models of immune reactions in skin”, from Proctor and Gamble, while Prof Sheila MacNeil is also part of a consortium who have been awarded £2.9M for “E-TERM, Engineering Tissue Engineering and Regenerative Medicine”. Dr Russell Goodall led a team, along with Prof Panos Tsakiropoulos and Dr Iain Todd as part of a large European Consortium to win a £440k FP7 grant “Accelerated Metallurgy”.
Our staff are regularly recognised with awards in recognition of their outstanding work. This year, Prof Allan Matthews was awarded the IOM3 Gold Medal. The award is given for a company, team or individual who has made a significant contribution to the industrial application of materials, in Allan’s case it was for transferring laboratory-based surface engineering technologies to industry. This is a remarkable achievement while also leading the Department as Head for the four years 2007-2011, arguably the most
1 Introduction
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successful in the Department’s history. In the same year, Dr Brad Wynne has been awarded the IOM3 Harvey Flower Titanium Prize for his ground breaking work on crystallographic texture evolution and phase transformation behaviour in aerospace titanium alloys. We were delighted for Iain Todd and Russell Hand, who were both promoted to Personal Chairs, for Dr Steve Matcher who was promoted to Reader and to Dr Russell Goodall and Dr Martin Jackson who were promoted to Senior Lecturer.
After years of steady academic staff numbers, we have made a number of key strategic appointments. We welcome John Provis from Melbourne University as Professor of Geopolymers. John’s research is primarily based around the design, synthesis and characterisation of durable, low CO2 materials for applications in construction, waste management and as low cost ceramics. Dr Karl Whittle joins us from ANSTO, Australia, as Senior Lecturer in Nuclear Materials. Karl’s research is concerned with the development of materials that have applications as first wall materials, and materials that have applications as both nuclear fuels and waste form. Dr Biqiong Chen has joined us from Trinity College, Dublin as Senior Lecturer in Functional Polymers. Her research is wide ranging, encompassing polymer chemistry, nanocomposites, biocomposites, biomimetics and nanofabrication. We are also delighted to appoint Dr Julian Dean as Teaching Fellow in January, to assist with Cross-Faculty
teaching, other parts of the curriculum and to continue his impressive research focused on modeling. Julian is a previous winner of the Kroto Prize for Excellence in the Science Education of Young People.
One of our key roles is the training of the next generation scientists and engineers at all levels from undergraduate to postgraduate. The last year has seen a substantial increase in numbers of research staff, research students and postgraduate Masters students. The total number of research students in the department is just short of 200, almost double the number 3 years ago. The same is true for the Masters students, with an intake of around 66 being more than double the numbers of three years ago. We now struggle for space for all the staff and students, but an ambitious multi-million pound new build and refurbishment programme in the Faculty of Engineering will help us build the infrastructure in-line with our plans for growth. Our success has been recognised with the Department being ranked the 2nd best Materials Department in the UK in both the Guardian and the Independent league tables, and of course we are proud to be part of 2011 University of the Year.
Prof WM Rainforth, Head of Department.
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2 Staff in the Department of Materials Science and Engineering
Head of Department:Prof W M Rainforth m.rainforth@ 0114 2225469 Materials Science and Engineering
Professors:Prof M R J Gibbs m.r.gibbs@ 0114 2224261 Materials PhysicsProf R J Hand r.hand@ 0114 2225465 Glass Science and EngineeringProf J H Harding j.harding@ 0114 2225957 Materials SimulationProf J W Haycock j.w.haycock@ 0114 2225972 Cell and Tissue EngineeringProf N C Hyatt n.c.hyatt@ 0114 2225470 Nuclear Materials ChemistryProf B J Inkson Beverley.inkson@ 0114 2225925 NanomaterialsProf S MacNeil s.macneil@ 0114 2225995 Cell and Tissue EngineeringProf A Matthews a.matthews@ 0114 2225466 Surface EngineeringProf J Provis (from 1st June 2012) Cement, Materials Science and EngineeringProf I M Reaney i.m.reaney@ 0114 2225471 CeramicsProf D C Sinclair d.c.sinclair@ 0114 2225974 Materials ChemistryProf I Todd i.todd@ 0114 2226011 MetallurgyProf P Tsakiropoulos p.tsakiropoulos@ 0114 2225960 MetallurgyProf G Ungar g.ungar@ 0114 2225457 Polymers and Organic MaterialsProf A R West a.r.west@ 0114 2225501 Electroceramics and Solid State Chemistry
Readers:Dr D A Allwood d.allwood@ 0114 2225938 Materials PhysicsDr S J Matcher s.j.matcher@ 0114 2225994 Biomedical EngineeringDr G Möbus g.moebus@ 0114 2225512 Microscopy and Materials ScienceDr E J Palmiere e.j.palmiere@ 0114 2225978 Metallurgy Dr I U Rehman i.u.rehman@ 0114 2225946 Biomedical Materials
Senior Lecturers:Dr B Chen biqiong.chen@ 0114 2225958 Functional PolymersDr C K Chong c.k.chong@ 0114 2225984 Biomedical EngineeringDr R Goodall r.goodall@ 0114 2225977 MetallurgyDr M Jackson martin.jackson@ 0114 2225474 Solid State ProcessingDr A Leyland a.leyland@ 0114 2225486 Surface TechnologyDr K P Travis k.travis@ 0114 2225483 ModellingDr K Whittle k.r.whittle@ 0114 2225929 Nuclear MaterialsDr B P Wynne b.wynne@ 0114 2226026 Metallurgy
Lecturers:Dr F Claeyssens f.claeyssens@ 0114 2225513 Biomaterials Dr C Freeman c.l.freeman@ 0114 2225965 Materials SimulationDr S A Hayes s.a.hayes@ 0114 2225516 Aerospace Materials and EngineeringDr G Hrkac g.hrkac@ 0114 2226028 Materials SimulationDr H Kinoshita h.kinoshita@ 0114 2225930 Materials Chemistry and GeochemistryDr N A Morley n.a.morley@ 0114 2225935 Materials PhysicsDr G Reilly g.reilly@ 0114 2225986 Tissue Engineering Dr C Rodenburg c.rodenburg@ 0114 2225921 Materials ScienceDr R P Thackray r.thackray@ 0114 2225963 SteelmakingDr X Zeng x.zeng@ 0114 2225948 Polymers
University TeachersDr J Dean j.dean@ 0114 2225928 Dr J Foreman j.foreman@ 0114 2225517 Dr P Kapranos p.kapranos@ 0114 2225509Dr M C Stennett m.c.stennett@ 0114 2225504
EPSRC Fellowship and Lecturer ElectDr T Hayward t.hayward@ 0114 2225499
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Emeritus Professors: Associate Professors:Prof B B Argent Prof P V HattonProf M Cable Prof R van NoortProf H A Davies, FREng Prof F G F Gibb Associate Senior Lecturer:Prof G W Greenwood, FRS, FREng Dr D H KirkwoodProf F R Jones Prof H Jones Associate Reader:Prof J M Parker Dr D H WarringtonProfessor C M Sellars, FREng Professor J H Sharp Associate Lecturers:Professor P V Wright Dr A W Bryant Dr A J Devlin
Visiting Lecturers: Dr E Maddrell (1 January 2007-31 December 2012) Senior Experimental OfficersDr V Royds Dr P Korgul (Sorby Centre)
Departmental Technical Manager: Experimental Officers: Dr S J Mason Dr L Ma Dr N Reeves-McLaren
Financial Administrator: Dr C Shaw Mr D M Binns Dr P Zeng
Short Course Director: Teaching Administrator:Dr P A Kapranos Mrs T V Sampson
Manager, Mercury Centre: The Nanolab Project Administrator: Dr M I Highett Mrs J Simpson
Marketing and Administration Officer/ Mercury Project: Project Engineer:Mrs S Hollely Dr F Derguti
Project Manager – Metals DTC: Research Manager: Dr C Hinchliffe Mr G Brown
Learning Technologist – Metals DTC: IMMPETUS Administrator:Mrs K Thomson Ms M Szofer
E-Futures DTC Programme Manager:Dr N J Lowrie
Visiting Academic Staff:Prof N A Chapman, Independent Consultant in Radioactive Waste ManagementProf P T Curtis, DSTLProf S Franklin, Philips, The Netherlands Prof K Holmberg, Technical Research Centre of Finland (VTT) Prof A A Howe, Tata Steel Prof D Jiles, Dept of Electrical & Computer Engineering, Iowa State University Prof P T McGrail, Composites and Polymers Consultant Dr S Owens, National Nuclear Laboratory Prof D Porter, Dept of Zoology, University of Oxford Prof S Stipp, University of Copenhagen, Denmark Prof W Smith, CCLRC Daresbury Laboratory (retired February 2011) Prof J Talamantes Silva, Sheffield Forgemasters Ltd Prof J Thomason, Strathclyde University Prof B S Yilbas, King Fahd University of Petroleum and Minerals, Saudi Arabia Associate Professor Qi-Long Zhang, Materials Science and Engineering, Zhejiang University Prof dr ir Sybrand van der Zwaag, Technische Universiteit Delft, The Netherlands
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Technical Staff: Support Staff: Dr J Bates Mrs V M Dalton (PA to Head of Department)Miss D Bussey Mrs K A Burton Mr M Carter Ms W B Dutton Mr M G Cooper Miss R D Fearon (p-t) Mr F G Fletcher Miss K L Heard Mr P Hawksworth Miss F E Kirk Mr D Haylock Mrs L C Mason Dr L Holland Mrs A Newbould (p-t)Miss C Johnson Mrs S Nixon (p-t) Mr R Kangley Miss K OrgillMs B C Lane Mrs A E Sargent Mr A G Mould Mr B G Palmer Coffee Bar Staff: Mr P Staton Mrs A Marquis Mr M J WagnerMr I P Watts
Research Fellows and Research Assistants: Dr M Audronis – EPSRC and Technology Strategy Board (AL) 20 Feb 2012-19 Feb 2013Dr A J Beck - BBSRC (AM) 1 Apr 2006–31 March 2012Mr U Bhatta – EPSRC (GM) 30 April 2010-14 March 2013Dr P Bingham – KTA (RJH) 1 Aug 2010–31 Dec 2011Dr K Briston – EPSRC (BJI) 01 Oct 2010–30 Sept 2012Dr M Bryan – EPSRC (DA) 1 March 2009–31 March 2012Dr A Bullock – Sheffield Teaching Hospitals Trust (SMN) 25 April 2000-22 April 2011Mr K Butler – European Union (JHH) 1 Dec 2009–31 May 2012Dr B Christiansen – EPSRC (JHH) 1 Oct 2010-30 Sept 2013Dr C Corkhill – EU REDDUP (NCH) 1 Sept 2011-31 March 2014Dr D Cumming – EPSRC (IMR) 1 March 2010-31 Oct 2012Mr R Delaine-Smith – P/T (SMN) 1 Oct 2011-27 April 2012Ms P Deshpande – Wellcome Trust (SMN) 16 July 2010-15 July 2013Dr R Dost – EPSRC (DA) 1 Dec 2011-20 July 2012Dr M Faraji – EPSRC (PT) 1 Jan 2009-31 Dec 2012Dr M Ferrarelli – Feb 2009-Feb 2012 Dr H Foxhall – EPSRC (JHH) 1 July 2010-30June 2013Dr A Gandy – EPSRC (NCH) – 1 Oct 2011-30 Sept 2013Mr J Ghatak – EPSRC (GM) 10 Jan 2011-31 Dec 2011 Dr W Guan - EPSRC (BJI) 1 July 2009-15 Jan 2012Dr E Hadzifejzovic – EPSRC (ARW) 1 Dec 2011-30 Sept 2012Dr J S Hinton EPSRC (WMR) 1 April 2009-31 March 2012Dr C Huang – Mercury Project (WMR/IT) 7 Feb 2011-30 Sept 2013Mr J Hunt – Mercury Project (WMR/IT) May 2011-Swept 2013Dr YN Kok – EPSRC (AL & AM) 1 June 2010-30 Nov 2011Dr M Krzyzanowski – EPSRC (WMR) 1 Aug 2002-31.12.2012Dr H Li TST (AL) 6 Feb 2012-5 Feb 2014Dr M Li – EPSRC (DCS) 1 April 2010-1 Setp 2012Dr F Liu – FP7-Nanogold (GU) – 2 Oct 2009-31 Aug 2012Mr Y Liu – EPSRC (ARW) – 1 Nov 2009-31 May 2012Mr Z Liu – Mandeville of London (FRJ) 1 Dec 2010-31 May 2011Dr A Lockwood – EPSRC (BJI) 1 Oct 2010-30 Sept 2012Dr Z Lu – EPSRC (SJM) 16 June 2008-31 May 2012Dr N Maso Carcases – EPSRC (ARW) 1 March 2009-30 Sept 2012Dr S Mittar – EU Cascade (SMN) 1 Feb 2011-31 Dec 2011Dr A Nogiwa Valdez – Mercury Project (WMR/IT) 1 March 2011-31 Sept 2013Dr I Ortega – Wellcome Trust (SMN) 10 Jan 2011-9 Jan 2012Dr J Pokorny – EPSRC (IMR) p/t– 1 Feb 2008-31 Jan 2012Mr A Rana – Mercury Project (WMR/IT) 1 May 2011-30 Sept 2013Mr T Sebastian – KTA (IMR) 1 April 2011-31 May 2012Dr F Sefat – Wellcome Trust (SMN) 5 Jan 2011–4 Jan 2014Dr J Sharp – EPSRC (WMR) 1 Dec 2010–30 Sept 2012
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Dr W Shen – EPSRC (IMR) 20 March 2010-19 March 2012Dr A Sidambe – ERDF (WMR & IT) 8 Sept 2010-07 Sept 2013Mr T Simm – EPSRC (WMR) 31 Oct 2011-31 Dec 2012Dr D Stapleton – Mercury Project (WMR/IT) 1 Oct 2011-30 Sept 2012Dr I Sterianou – EPSRC (IMR) 1 Oct 2009-30 Sept 2012Dr T Swait – Airbus (SAH) 1 Feb 2010-27 July 2012Dr M Thomas – EPSRC/UoS Doctoral Prize Fellowship – 1 Oct 2011-30 Sept 2012Dr C Utton – EPSRC (PT) 8 June 2010-30 April 2014Dr A Yerokhin – EPSRC (AM) 1 July 2003-31 March 2013Dr H Zhang – (IMR/WMR) 12 Dec 2011-31 Aug 2014Dr Y Zhang – Mercury Project (IT/WMR) 1 Aug 2011-31 Sept 2013
KTP Associates: Dr T Biggs – KTP Rolls Royce (RG) Dr M Darby – KTP from Ilika Technologies Ltd (IMR) 1 Feb 2009-31 Jan 2012Dr R Deffley – KTP from LPW Technology Ltd (IT) 1 Aug 2010-31 July 2012Mr L Jiranek – KTP from William Beckett Plastics (IT & RG) 1 Nov 2010-30 Oct 2012Mr S Saeidi – KTP from Cutting & Wear Ltd (AL) 17.01.2011-16.04.2013Dr P Travaglia – KTP from DPG Ltd (SAH) 1 March 2010-29 Feb 2012Miss B Zalinska – KTP from Sarantel Group plc (IMR) 1 Oct 2009-30 Sept 2012
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3 Industrial Liaison Committee
Chairman Dr M J May [Mick] Gilleycroft31 Vicarage LaneDoreSheffield S17 3GX Tel: 0114 [email protected]: 07739219492
MembersDr R Dolby[Richard] 25 High StreetBurwellCambs CB25 0HDTel: 01638 [email protected]
Dr G Bridge Aesseal plcMill CloseTempleboroughRotherham S60 [email protected]
Dr G Fairhall[Graham] Chief Technology OfficerNational Nuclear LaboratorySellafieldSeascaleCumbria CA20 1PGTel: 01946 [email protected]
Dr C Griffiths[Carl] Biofusion plcSheffield Bionincubator40 Leavygreave RoadSheffield S3 7RDTel: 0114 275 5555Fax: 0114 275 [email protected]
Dr R Hardeman[Rob] Seagate Technology (Ireland)1 Disc DriveSpringtown Industrial Estate Londonderry BT48 0BFTel: +44 28 7127 [email protected]
Dr J Hicks[John]Wound ManagementSmith & Nephew101, Hessle RoadHull HU3 [email protected]
Miss E M Holt[Liz] Research ScientistJohnson Matthey Technology CentrePO Box 1Belasis AvenueBillinghamTS23 1LBTel: 01642 [email protected]
Dr A J Hosty[Andrew] CEO – Technical Ceramics DivisionThe Morgan Crucible Company plcQuadrant55-57 High StreetWindsorBerkshire SL4 1LPTel: 01753 837000Fax: 01753 [email protected]
Dr D Kells[Dan] BAE SystemsAdvanced Technology CentreSowerby BldgPO Box 5, FPC 267FiltonBristol BS34 7QWTel: 0117 3028235M: 07793 421 [email protected]
Dr S Pike[Simon] Manager, Continuous Improvement and Business ExcellenceCorus Long ProductsPO Box 1, Brigg RoadScunthorpe DN16 1BPTel: +44 (0) 1724 402308M: +44 (0) 7808 [email protected]
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Dr B Rickinson[Bernie] Chief ExecutiveInstitute of Materials1 Carlton House TerraceLondon SW1Y 5DBTel: 020 7451 [email protected]
Dr R Ricks[Ricky] Technology Strategy ConsultantsUnit 16, Blackwell Business ParkBlackwellShipston-on-StourWarwickshire CV36 4PETel: 01608 682199M: 07739 [email protected]
Dr E G Shahidi[Ebby] Advanced Composites Group LtdComposites HouseSinclair CloseHeanor Gate Industrial EstateHeanorDerbyshire DE75Tel: +44(0) 1773 766200Mobile: +44 (0) 7887 [email protected]
Dr M W Stow[Martin] Vice President R&D WW, Ethicon Productsc/o DePuy International LtdSt. Anthony’s RoadLeeds LS11 8DTTel: +44 (0) 113 272 4110Fax:+44 (0) 113 387 6218 Mobile: +44 (0) 7768 555 707Email: [email protected]
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4 Academic Staff Profiles
Dr Dan A Allwood
BSc PhD MInstP CPhys
Reader in Materials Physics
Research centres on the understanding, analysis and application of patterned magnetic nanostructures and, in particular, magnetic domain walls in nanowires. Research uses both experiment and modelling, and consists of four main themes. Nanowire devices for information technology (e.g. memory) and biological applications (e.g. cell templating) are being developed. The study of how magnetic structures can interact with laser-cooled atoms hopes to lead to new stable platforms for quantum computation. New magneto-optical analytical techniques are being developed to improve the resolution and sensitivity of measurements of magnetic nanostructures.
Dr Biqiong Chen
BSc, MSc, PhD
Senior Lecturer in Functional Polymers
Research focuses on synthesis, processing, characterisation and properties of polymers and polymer nanocomposites with particular emphasis on the structure-property relationships. Current research activities include fundamental studies of polymer-clay and polymer-graphene nanocomposites; plastics recycling; development of biomimetic polymer nanocomposite foams as potential tissue scaffolds; novel nanocomposite hydrogels for engineering applications; biodegradable microneedles for transdermal drug delivery; functionalised nanoparticles for cancer imaging and treatment; and stimulus-responsive nanocomposites.
Dr Chuh K Chong
BSc PhD
Senior Lecturer in Biomedical Engineering
Main research interest centres on cardiovascular fluid mechanics, focusing on understanding the role of haemodynamics in the pathogenesis of arterial diseases in normal and reconstructed vessels, the pharmacokinetics of drug-eluting stents, with the aim of designing better-performing customised vascular implants and bypasses. Another interest is in tissue engineering, particularly the cardiovascular system, focusing on the mechanics of soft tissues, developing functional cell-seeding device and bioreactors, scaffolds and matrices with desired architecture and material properties, with the aims of understanding the effects of materials, mass transport, biochemical cues and mechanical stresses on cell activities in purpose-designed bioreactors to develop better tissue constructs.
Dr Frederik Claeyssens
Licentiate PhD Member RSC MRS
Lecturer in Biomaterials
Current research is focussed on biomaterials manufacture with laser based techniques. This research broadly falls into three categories: Coatings for biology: Biocompatible surface coatings of semiconductors to be integrated into cell-silicon interfaces for biosensors. Bioprinting: Laser based techniques for printing biomolecules/cells for producing biomolecule arrays and biosensors. Biomaterials manufacture via microstereolithography: Production of microstructured biomaterials for usage as tissue engineering scaffolds, via a laser based photocuring technique. Via scanning the laser through a photocurable resin, user-defined microstructures can be produced from a biocompatible polymer. This technique can be combined with self-assembly approaches to achieve hybrid biomaterials as 3D scaffolds for implants, tissue engineering and pharmaceutical testing.
Prof Michael R J Gibbs
BSc PhD CPhys FInstP MIEEE
Professor of Materials Physics and Director of the Centre for Advanced Magnetic Materials and Devices
Current research includes: the study of magnetoelastic materials, bulk and thin film; the study of permanent magnet thin films; the study of magnetic microelectromechanical systems (MagMEMS); the application of magnetic materials in sensors and actuators; the study of materials for applications in spintronics; the study of the principles and application of magnetic force microscopy.
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Dr Russell Goodall
MEng PhD CEng MIMMM
Senior Lecturer in Metallurgy
Principal research interests are in the processing, mechanical and thermal properties and applications of open-celled porous metals. This includes aluminium, which with a relatively high thermal conductivity, combined with low density and low cost is interesting for applications requiring heat transfer from or to a fluid medium. Open-cell foams made from other metals such as titanium can have applications as electrodes or as surgical implants, amongst many others. As well as foams (with pores or cells in random locations), he is also interested in porous structures with varying degrees of order, such as 3D lattice structures. Current challenges are the assessment of the suitability of processes for practical fabrication of foam parts, the development of methods to allow production of novel foam architectures, the characterisation of both the mechanical and thermal performance of the material and the further optimisation of the properties for certain applications.
Prof Russell J Hand
MA PhD MEd CPhys CEng FSGT
Professor of Glasses and Ceramics; Sub-Dean for Undergraduate Affairs, Faculty of Engineering
Research interests focus on the mechanical properties of ceramics and glasses. He has on-going research on the vitrification of radioactive and toxic wastes using borosilicate and other glasses. He is also interested in the use of glassy wastes in secondary applications. Other work includes the development of chalcogenide glasses for sensor applications, glass ceramics for dental applications and mechanical property-composites relations in silicate glasses.
Prof John Harding
MA PhD CPhys FRSC FinstP
Professor of Materials Simulation
Current research includes the development of methods to simulate atomistic processes with long timescales and their application to problems in bulk ceramics and at interfaces; simulation of the structures of interfaces of ceramics; simulation of organic/inorganic interfaces, nucleation and self-assembly (particularly in the context of biomineralisation and biomimetics); simulation of nanomaterials; mesoscale simulation of plasma-sprayed coatings. He is the organiser of an annual Summer School in Molecular Simulation.
Prof John W Haycock
BSc PhD
Professor of Cell and Tissue Engineering
Research interests in bioengineering which span 3 key areas: 1) Bioactive surfaces - controlling the behaviour of skin and nerve cells with adhesive, migratory and anti-inflammatory peptides; 2) Nerve tissue engineering - the integration of bioreactors and nerve guidance channels for repairing nerve injury, and the use of stem cells for glial cell differentiation and 3) Skin tissue engineering - the use of synthetic fibre scaffolds and human skin cells for 3D in vitro models to detect toxic and inflammatory compounds as an alternative to animal models.
Dr Simon A Hayes
BEng PhD
Lecturer in Aerospace Engineering
Research interests encompass smart materials, nanocomposites and nanomechanical property determination. He is involved in the development of sensors for damage detection, cure monitoring and through-life environmental condition monitoring in polymer-matrix composites. He has also developed a patented technology for the healing of damage within composite structures. He has projects examining the mechanical properties of clay and nanotube-based nanocomposites. He is also involved in the development of nanoindentation for the analysis of soft viscoelastic materials.
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Dr Gino Hrkac
Dr techn Dipl INg
Royal Society University Research Fellow
Main research area is computational and theoretical magnetism, and especially the development of a numerical model to investigate and predict the behaviour of magnetic spin valve systems and the effect of eddy currents in nano-scale materials. He is working on the theoretical and numerical description of spin electronic devices on a length scale ranging from the computation of the local spin current density and magnetization dynamics with a sub-nm resolution in micron size devices (magnetic nano pillars and Magnetic Tunnel Junctions). A prominent example for his work is the theoretical explanation of the angular dependency of phase locking phenomena in point contacted spin valves and His work on the simulation of spin current induced magnetization dynamics that explained the low frequency oscillations found in point contact devices that were explained by vortex oscillations. His latest research includes ab initio simulations of atomic structures, solid state molecular dynamics for the simulation of the transition of amorphous to crystalline grain boundaries in NdFeB magnets within the framework of an industrial funded project on permanent magnets (European-Japanese consortium).
Prof Neil Hyatt
BSc PhD MInstP
Professor in Materials Chemistry
Research is focussed on the understanding of structure – property relationships in the solid state and the application of diffraction techniques under extreme (high pressure/temperature) conditions. Current areas of research interest include the synthesis and characterisation of dielectric and ferroelectric materials; the immobilisation of high level nuclear waste in glass and ceramic matrices; structural studies of the vitreous state; pressure induced spin state transitions in perovskite related oxides; and the synthesis of new materials under extreme conditions.
Prof Beverley J Inkson
MA PhD
Professor of Nanomaterials
Research interests focus on the mechanical and functional properties of metals and ceramics at the nanoscale, quantifying how nanostructures and surfaces behave differently from conventional bulk materials and evolve with time. Current projects include in-situ dynamics of nanostructures and nanofluids, nanoscale friction and energy transfer, nanoelectrical properties including nanobatteries, nanocarbon, technologies for nanoscale joining/welding, nanoceramics for oral care, and advanced nanocharacterisation (3D TEM/SEM/FIB, tomography, in-situ TEM and SEM, nanoindentation).
Dr Martin Jackson
MEng PhD DIC
Royal Academy of Engineering/EPSRC Research Fellow and Lecturer Elect
Research interests centre on solid state processing, microstructural/textural evolution and phase transformations in light alloys. Major research focus is development of low cost non-melt consolidation routes for particulate titanium-based feedstock from emerging reduction processes. Current research in titanium also includes; (i) microstructural evolution during isothermal forging of high strength alloys used in airframe forgings; (ii) alpha case formation/crack initiation in alloys used in aeroengine gas turbine compressors. Other research interests include the superplastic behaviour of aluminium and magnesium alloys during processing for automotive applications.
Dr Hajime Kinoshita
BEng MEng DEng
Lecturer in Materials Chemistry and Geochemistry
Current researches focus on the environmental-friendly applications of mineral-based materials, extending from nuclear waste management to CO2 storage. Current projects include low temperature synthesis of ceramics for nuclear waste immobilisation, CO2 storage in recycled cementitious waste materials using molten salt media. Based on thermodynamics, both experimental and computational techniques are used to improve their capacity to host the aiming compounds and the compatibility of the products to the environment.
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Dr Adrian Leyland
BSc PhD MInstP
Senior Lecturer in Surface Technology
Research interests are focused on Surface Engineering and Tribology, specialising in plasma-assisted Physical Vapour Deposition (PVD) of nanostructured ceramic coatings (for wear resistance and/or adaptive behaviour in extreme environments), metallic nanocomposite/glassy-metal coatings (for combined wear and corrosion protection), duplex plasma-diffusion/ PVD-coating treatments (to improve the load-bearing capacity of light alloys and stainless steels in sliding wear applications) and the development of tribological testing/property evaluation techniques for coatings.
Prof Sheila MacNeil
BSc PhD
Professor of Tissue Engineering
Primary research interests are the production of tissue engineered skin and oral mucosa and corneal tissues for clinical application. Additionally, research has led to the development of a wide range of 3D tissue engineered epithelial models which are being used to investigate a range of normal and disease conditions. Some of the groups’ current tissue engineering challenges for translation to the clinic are developing a carrier for delivery of cultured corneal epithelial cells for diseases of the cornea, developing tissue engineered materials for repair of the pelvic floor in woman suffering from stress incontinence and developing new approaches to a one stage in theatre approach to producing split thickness skin for elective surgery applications.
Dr Stephen J Matcher
BSc, PhD, Member SPIE, OSA, BMS, ESM.
Reader in Biomedical Engineering.
Current research interests: development of optical imaging and spectroscopy to characterize bioengineered tissues in vitro and in situ. Main techniques are optical coherence tomography and microscopy, elastic scattering spectroscopy, second-harmonic and two-photon microscopy. He is particularly interested in the collagen structure of connective tissue and how this is altered in disease, in techniques to assess tissue perfusion and cellular bioenergetics in vivo and in Doppler techniques to study the microcirculation.
Prof Allan Matthews
BSc PhD FIMMM FIMechE FIET FIMF
Professor of Surface Engineering
Main research interests involve plasma-based surface coating and treatment processes, and techniques for surface characterisation and evaluation. Current projects include the deposition of nanocomposite tribological coatings by sputter-deposition, the surface modification of lightweight metals by plasma electrolytic oxidation, low-temperature deposition of phase-stabilised oxide ceramic coatings, and plasma diagnostics and control studies. He is also involved in the development of computer-based coating selection systems.
Dr Günter Möbus
DiplPhys Dr rer nat (PhD)
Reader in Microscopy and Materials Science
Research is focussed on the characterisation of materials on the atomic and nano-scale, including development of quantitative electron microscopy techniques for 3D-mapping of microstructure, composition, strain, and retrieval of crystal defect structures. Within the context of immobilisation science, modern characterisation techniques, such as tomography, 3D reconstruction, and fine structure spectroscopy are used to detect the local composition and microstructure in glasses and ceramics, and to determine local coordination and oxidation states of cations.
Dr Nicola A Morley
MPhys PhD MemInstP
Lecturer in Materials Physics
Current research includes: manipulating the anisotropy and magnetostriction of thin Fe-based magnetic films and multilayers; novel spintronic devices, which include organic polymer spacer layers; spinterface investigations at organic-magnetic interfaces; organic intrinsic magnetoresistance of conjugated polymers and small-molecules; using muons to measure the intrinsic transport properties of polymers.
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Dr Eric J Palmiere
BSc MSc PhD CEng
Reader in Metallurgy
Research involves the microstructural evolution, and the subsequent development of mechanical properties, during the thermomechanical processing of both ferrous and nonferrous alloys with a primary focus on ferrous alloys such as stainless, microalloyed steels and associated model alloy steels. He is particularly interested in developing a basic understanding between those softening (i.e. recovery, recrystallisation) and strengthening (i.e. solid solution formation, precipitation) mechanisms which occur either in austenite or in ferrite.
Prof John Provis
BE(Hons) BSc PhD
Professor of Cement Materials Science and Engineering
Research interests are focused on the development and analysis of novel methods to optimise the technical and environmental performance of cements, concretes and related materials. Current projects include nanostructural and microstructural analysis of low-CO2 alkali-activated cements through the application of beamline and laboratory techniques, modelling of chemical reaction and transport processes involved in materials synthesis and utilisation, and the development and validation of reliable durability tests for the prediction of long-term performance of materials and structural elements.
Prof W Mark Rainforth
BMet PhD FIMMM FRMS CEng FInstP CPhys
Head of Department and Professor of Materials Science and Engineering
Research focuses on developing a mechanistic understanding of microstructural evolution as a basic pre-requisite to the development of physically based modelling of both metals and ceramics. Huge gains have been made in the quantification of microstructure across the length scales, including field emission gun TEM techniques for determining chemical and physical structure at the atomic scale, focussed ion beam (FIB) microscopy for the determination of surface structure (e.g. oxides) and high resolution back-scatter electron diffraction (EBSD) for texture and phase distribution analysis. Such techniques are applied to the structure of nanoscale coatings, the evolution of deformation and precipitation substructures during hot working, and surface structures developed through friction and high temperature exposure.
Prof Ian M Reaney
BSc MSc PhD MInstP FRMS CPhys CEng
Professor of Ceramics
Main research theme is the use of transmission electron microscopy and Raman Spectroscopy to study the structure and microstructure of electroceramics as well as the development of new or improved materials for commercial applications. His research activities are mainly concerned with dielectric resonators for microwave communications as well as materials for sensor and actuator applications. He also has interests in glass ceramics for biomedical applications.
Dr Ihtesham ur Rehman
BSc MSc PhD
Reader in Biomedical Materials
The focal point of his research has been the identification and understanding of the fundamental mechanisms by which chemical responses are mediated by nan- to micro-scale variations in biomaterials, with the main emphasis on the development of synthetic inorganic bone analogue materials and characterisation of natural tissues. Current research covers the following themes:
Analysing Cancer with Spectroscopy: FTIR and Raman spectroscopy of cancer tissues and cells with the aim of developing diagnostic techniques for cancer.
Polymers and Bioactive Composites: Development of an auxetic biodegradable drug-eluted stent-graft in the palliation of oesophageal cancer Bioactive composite materials: Development of improved ceramic/polymer composites for osteological and dental applications
Dental Materials: Glass -ionomers, nano-ceramics and nano-composites for dental restoration.
Dr Gwendolen Reilly
BSc DPhil
Lecturer in Tissue Engineering
Background: bone biomechanics; transduction of mechanically induced signals in bone cells; bio-active glasses as a scaffold for bone tissue engineering; skeletal cell differentiation. Research aims: investigating the use of mechanical stimuli to enhance strength of tissue engineered bone and cartilage; examining the effect of biomaterial scaffolds on skeletal cell mechanical responses; mechanical manipulation of tissue engineered matrix structures. Our laboratory is particularly interested in using tissue engineering to create 3D bone models for use as an alternative to animal experiments in the testing of orthopaedic pharmaceuticals and devices.
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Prof Derek C Sinclair
BSc PhD CChem MRSC
Professor of Materials Chemistry
Research interests are primarily involved with the synthesis and characterisation of oxide-based electroceramics. Current work includes investigating composition-structure-property relationships in important electroceramics, explorative phase diagram studies and speculative synthetic work on ‘new’ materials with superior electrical properties. The latter approach is being used to discover new mixed ionic/electronic conductors, proton conductors, microwave dielectrics, ferroelectrics, thermo-electrics, piezo-electrics and low temperature co-fired ceramics. Recent work includes the co-electrolysis of CO2 and H2O to produce fuel (syn gas) from Solid Oxide Fuel Cells.
Dr Richard Thackray
BEng PhD DIC
Tata Steel Lecturer in Steelmaking
Research interests are in continuous casting of steel, in particular the role of mould powders in the processing route, where models have been developed which relate the viscosity, break temperature, and crystallinity of the powder to the successful performance of the casting operation. New research into evaluating the suitability of F-free fluxes to replace existing fluxes will also be carried out in the near future. In addition, work to understand the complex flow of metal during the casting process, and the associated heat transfer effects and product quality implications, using process modelling techniques is also ongoing.
Prof Iain Todd
BEng PhD
Professor of Metallurgy and Research Director of the Innovative Metals Processing Centre
The development of novel processing technologies and metallic materials forms the core of his present research activity. Current work includes: the development of novel processes for the production of titanium components by powder metallurgical routes; modelling microstructure evolution during additive manufacturing processes; the manufacture of Ti components for biomedical applications and the kinetics of Bulk Metallic Glass formation and their physical properties. Work is conducted through the Innovative Metals Processing Centre and in collaboration with Industry and the Advanced Manufacturing Research Centre with Boeing at the University of Sheffield.
Dr Karl P Travis
BSc PhD CChem MRSC
Senior Lecturer in Modelling Materials
Research interests cover Theoretical and Mathematical Physics, particularly of condensed phases; structure-property relationships of materials; and the thermodynamic behaviour of nana-confined fluids. Research is currently focussed on applying atomistic, mesoscale and continuum modelling techniques to problems connected with the storage of nuclear waste. Some current topics under investigation include: modelling radiation damage in ceramic wasteforms, modelling the conductive flow of heat in very deep geological disposal scenarios and developing Dissipative Particle Dynamics for predicting phase behaviour and rheology in complex mixtures.
Prof Panayiotis (Panos) Tsakiropoulos
D Eng. Mining Eng. - Metallurgy, MMet, PhD
Professor of Metallurgy and POSCO Chair of Iron and Steel Technology
Research interests are in the design and development of ferrous and non-ferrous alloys and composites for the energy, transport and aerospace industries via process-microstructure-property studies. For example, the research includes materials that are suitable for airframe and landing gear applications as well as materials for high and ultra high temperature applications in gas turbines. Materials processing is also researched as part of the alloy development. The emphasis of the research is on establishing (i) the effects of processing on the microstructure and properties of structural engineering materials and (ii) how processing can be tailored to particular engineering requirements for desirable microstructures and properties. An essential part of the research is the study of nucleation in under-cooled alloy melts and solid state phase transformations in alloys and in situ composites to generate the underpinning science in the development of metallic materials. Currently, alloys of Fe, Mo, Nb, Ti and Zr are under investigation.
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Prof Goran Ungar
BSc PhD CPhys
Professor of Polymers and Organic Materials
Research interests include structure, phase behaviour and propertied of liquid crystals (LC), polymers and supramolecular systems, as well as inorganic-organic hybrids and metamaterials, based on LC in nanopores and LC-modified nanoparticles. Our speciality are highly complex structures with 2D or 3D order in dendrimers and amphiphilic compounds, and soft quasicrystals. We use X-ray (synchrotron) and neutron scattering, as well as different electron, scanning probe and optical microscopy techniques. Another research area is structure and morphology of semicrystalline polymers. This includes monodisperse model polymers in the form of ultra-long chain n-alkanes, biodegradable polymer fibres, and new crystallization mechanisms (e.g. “self-poisoning” crystallization).
Prof Anthony R West
BSc PhD DSc CChem CPhys FRSC FInstP FIMMM FRSE
Professor of Electroceramics and Solid State Chemistry
Current research includes: the development of new spinel cathode materials such as LiCoMnO4 for lithium batteries; synthesis and characterisation of new ferroelectrics and relaxor ferroelectrics with tetragonal tungsten bronze structure; new Li+ ion and O2- ion conducting solid electrolytes; structures of Mn-based complex perovskites and Bi pyrochlores; probing the structure-property correlations that control the performance of zinc oxide varistors, barium titanate PTCR devices and CaCu titanate barrier layer capacitors. He is also well-known for his books on Solid State Chemistry.
Dr Karl Whittle
BSc MSc PhD
Senior Lecturer
Research focusing radiation effects and how they can be mitigated in the development of new materials for use within nuclear reactors (fission and fusion), and the next generation of nuclear waste forms. An approach using experimental investigations coupled with computer simulations are used ‘holistically’. Current topics include order/disorder in systems and how it can be used to tailor radiation effects, transmutation effects, and new materials resistant to 400 dpa (displacements per atom) of damage.”
Dr Bradley P Wynne
BEng PhD
Senior Lecturer in Metallurgy
Research interests focus on the thermomechanical processing of metals and alloys, particularly the interrelationship between the constraints imposed by the deformation conditions and the constraints on flow behaviour generated by crystal structure and crystallographic texture, which in turn determines deformation microstructure evolution. Currently his major focus is on the effects of non-linear strain paths on microstructure evolution. The overall aim of this research is to develop true internal state models for microstructure evolution to replace our current empirically based models which are often inadequate when deformation conditions are complex.
Dr Xiangbing Zeng
BSc MSc PhD
Lecturer in Polymers
Current research concerns 1-d, 2-d, 3-d ordered nano-structures (1 – 100 nm) in macromolecular and supramolecular systems, with potential applications for molecular electronics, photonics etc. The main methods used are small angle x-ray and neutron scattering (SAXS and SANS). These experiments are often carried out in real-time in order to catch transient structures and rapid transformations such as occur in real-life, industrial processing of polymers.
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5 Research Highlights
5.1 Biomaterials and Tissue EngineeringBioengineering peripheral nerveThree-dimensional in vitro cell culture models are seeing a rapid rate of development, principally driven by the need for conducting studies in a more relevant environment compared to the culture of cells in two dimensions, against a background of the 3Rs (replacement refinement, reduction) in regards to animal usage and scientific experimentation (reviewed by John Haycock (Methods Mol Biol 2011;695:1-15). While an increasing number of mammalian tissues have been reconstructed using three dimensional techniques, often by combining scaffolds and the co-culture of cells, little work has been conducted on peripheral nerve. The development of such models holds considerable value for a breadth of studies, from a basic understanding of neuronal-glial development through to the design of improved scaffolds for nerve tissue reconstruction following injury. It is known that an intimate relationship exists between neurons and glia, both in development and following the response to injury. However, a number of specific requirements exist for making 3D in vitro models.
Thus, the design of scaffolds for controlling neuronal and glial cell movement requires an understanding of the cellular response to physical stimuli. Previous studies report that fibre diameter can alter cellular morphology and proliferation, as well as migration. In this respect, the use of electrospinning, while a commonplace technique for fabricating scaffolds, is attractive for studying the relationship between physical dimensions and cellular response. Fibre diameters can be controlled between nanometer and micrometer length scales by manipulation of the electrospinning processing parameters. Aligned fibres can be readily fabricated via a number of fibre collection strategies, which is of particular importance for peripheral nerve studies.
In recent research from John Haycock and colleagues (Muhammad Daud, Kiran Pawar, Frederik Claeyssens and Tony Ryan) we have developed a controlled process for producing aligned polycaprolactone (PCL) microfibers with discrete diameters ranging from 1 µm to 8 µm. The response of neuronal cells and primary Schwann cells were evaluated separately in single culture and as glial-neuronal co-cultures. This was then extended to using dorsal root ganglion cultures for forming aligned 3D neuronal-glial co-cultures. Taken together, the models formed a basic but organised peripheral nerve structure and we suggest this approach has the potential for use in a breadth of studies, from basic cell biology through to injury, in disease studies (e.g. de-myelinating disorders), but also in the improved design of biomaterial scaffolds for peripheral nerve regeneration and in bridging the gap between simple in vitro cultures and in vivo implantation studies.
Figure 5.1.1. – Left. Confocal microscopy images of neuronal cells (beta-III tubulin - red) and primary Schwann cell (S100β - green) co-cultures on aligned PCL fibres of 1 μm (A, D, G, J), 5 μm (B, E, H, K) and 8 μm (C, F, I, L) diameter after 4-days co-culture. Images are shown as both separate channels - neuronal cells alone (A, B, C), primary Schwann cells alone (D, E, F) and neuronal / primary Schwann cell co-cultures (G, H, I). Corresponding 3D composite images are presented (J, K, L). Neurite growth and Schwann cell organization was guided in the direction of fibre alignment for all fibre diameters. Scale bar = 50 μm. Right - Confocal microscopy images of isolated DRGs grown on 1 μm (A-D), 5μm (E-H) and 8μm (I-L) aligned PCL fibres. Fibre direction is from left to right in all micrographs (A-L). (A, E, I) S100β expressing Schwann cells (green); (B, F, J) β-III tubulin expressing neurites (red) and (C, G, K) overlaid images showing co-localisation of β-III tubulin expressing neurites and S100β expressing Schwann cells. (D, H, L) shows high magnification selected regions of interest identifying close physical association of Schwann cells and neurites (yellow). Arrows for (A, E, I) indicate the furthest identified position of migratory Schwann cells. Arrows for (B, F, J) indicate the furthest position of neurite extension. Asterisks (*) mark the position on the left of each micrograph of where ganglion bodies were placed for culture. Scale bar = 100 μm. (M, N, O) shows isolated DRGs cultured on a flat (control) TCP surface for reference with no directional organisation, labelled for S100β (M), β-III tubulin (N) and S100β plus β-III tubulin (O). Sale bar = 200 μm. (P) Quantification of neurite length and Schwann cell migration on each of the fibre scaffolds.
Novel technique using stem cells revives damaged eye
Figure 5.1.2. This shows the before and after on a patient treated with a combination of their own tissue delivered as very small pieces from the other (undamaged) eye to the damaged eye on a substrate of human amniotic membrane. This is an example of a simple idea being translated into clinical practice.
Sheila MacNeil working with colleagues at the LV Prasad Eye Institute, Hyderabad, India, with funding supported by the Wellcome Trust has had the pleasure of seeing an idea going rapidly into clinical practice to benefit man. The project funded by the Wellcome Trust (Sheila MacNeil is PI and Frederik Claeyssens (Department of Materials Science and Engineering) and Professor Tony
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aterials and Tissue Engineering
Ryan (Department of Chemistry) are co-applicants on this) is seeking to develop a synthetic carrier membrane to use as an alternative to the biological donor membrane of the human amnion which is currently used to deliver laboratory expanded limbal stem cells to the cornea. While The use of the human amnion to deliver cells can work reasonably well, this project seeks to design a synthetic off-the-shelf safer alternative to the human amnion and work is proceeding well. However, during the initial planning phase of this research Sheila’s idea of using small explants of tissue rather than laboratory cultured cells was shared with her colleagues in India who quickly took the idea into progress putting very small explants of tissue onto the human amnion and the above picture shows an example of the clinical results. The relevance and impact of this technique is that it simplifies how these patients can be managed so that on no longer needs to laboratory expand the cells but may be able, for certain conditions to simply use finely diced explants of the contralateral undamaged eye. This is an example of an international research partnership benefiting patients.
Materials for 3D bone growthDisorders of bone are a group of serious diseases which particularly affect the aging population, inhibiting mobility and therefore incurring high costs to the NHS and social services. Bone tissue engineering aims to replace diseased or damaged bone and can create 3D models with which to test orthopaedic materials and pharmaceuticals. Bone cell behaviour depends on the surrounding material that the bone is attached to, so to replicate bone growth outside the body the correct proteins need to be available for the cells. Together with a company from Newcastle – Orla Protein Technologies, funded by METRC, we are working on a method to culture bone in 3D for use in investigating orthopaedic materials and pharmaceuticals. Orla specialise in protein coatings and arrange small components of proteins –peptides in well orientated configuration on 2D surfaces and 3D scaffolds. The aim is to develop a protein coating on a porous 3D glass scaffold which enhances bone cells growth and matrix formation to generate sufficient 3D matrix for testing. We are encouraged by the early data emerging from this project showing that bone-specific protein coatings encourage the cells to make more collagen and calcium, the major components of bone’s extracellular matrix and that these cells respond to a bone relevant mechanical stimulus, oscillatory fluid flow, by further increasing matrix production. Orla Protein Technologies aim to commercialise the optimised scaffold as a platform for orthopaedic testing.
(a) (b) (c)
Figure 5.1.3. (a) Bone cells in 3D glass scaffolds imaged by confocal microscopy. (b) Cross-section through glass scaffolds with bone matrix stained in red. (c) Oscillating fluid flow bioreactor to apply shear stress to bone cells.
Optical coherence tomography imaging of articular cartilage The successful treatment of osteoarthritis is challenging due to the poor healing capacity of articular cartilage. Osteoarthritis leads to a progressive loss of cartilage, the dominant component of which is type-II collagen. This collagen has a complicated 3-D zonal architecture which in combination with water and proteoglycans gives cartilage the required mechanical properties to withstand in-vivo stress distributions. Tissue-engineering approaches to osteoarthritis treatment are a promising alternative to more traditional methods such as total joint replacement, mosaicplasty or autologous chondrocyte implantation. Tissue-engineering typically uses a synthetic scaffold seeded with cells to try to regenerate a collagen matrix that is morphologically similar to the native tissue. Tools to measure the 3-D collagen structure of cartilage are thus needed, especially if these could be used longitudinally in-vivo to monitor the successful progress of the treatment.
Collagen structure is traditionally measured using destructive sectioning techniques such as scanning electron microscopy; picrosirius red stained light microscopy or polarized light microscopy. In-vivo techniques such as x-ray computed tomography or ultrasound do not have the resolution or contrast to resolve collagen fibres in cartilage. Diffusion-tensor magnetic resonance imaging can yield 3-D collagen orientation however water diffusion anisotropy in cartilage is weak and so the measurement takes hours, even with very high sensitivity systems.
Recently Steve Matcher and co-workers have developed a non-destructive form of polarized light microscopy known as variable-incidence-angle polarization-sensitive optical coherence tomography (Kasaragod, Lu, Jacobs and Matcher, Biomed Opt Express 3(3): 378-399 (2012)). This technique exploits the fact that collagen is optically birefringent and the degree of birefringence depends on the alignment between the fibres and the incident light beam. By using optical coherence tomography (a non-destructive reflection-mode imaging tool which is an optical analogue of ultrasound imaging) to measure the birefringence at various incident beam angles enough information can be extracted to solve the 3-D structure by an inverse method of iterative model fitting. Recently we have demonstrated that measured data from bovine cartilage is compatible with a model for angle-resolved birefringence based on the extended Jones matrix calculus when combined with structural data suggested by SEM work. The figure below compares measured (symbols) and calculated (red lines) depth-resolved optical retardance curves for bovine cartilage. The structural parameters such as the zonal thicknesses and the polar and azimuthal angles of the fibres have been optimized using a non-linear optimization algorithm,
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thus yielding estimates for these parameters which are consistent with the known structural properties of this type of cartilage. With further development we believe that this technique could become a unique tool for the in-vivo characterising of cartilage structure.
Figure 5.1.4. Comparison of measured (symbols) and calculated (red line) depth-resolved optical retardance curves for bovine cartilage.
A physiological flow-bioreactor system for stimulating vascular cells/tissuesMechanical forces are believed to be important in stimulating vascular cells and tissues and hence involve in the development of not only healthy and stable vascular tissues and vascular networks, but also vascular diseases including atherosclerosis and intimal hyperplasia. In these normal and pathological events, endothelial cell (EC) in particular, which is known to be sensitive to mechanical forces, is the center of attention. Many different mechanical parameters e.g., wall shear stress (WSS), temporal and spatial gradients in wall shear stress (TWSSG, SWSSG) and oscillatory flow (OSI) have been hypothesised to be important in determining the response of EC. Elucidating their individual and combined effects, however, requires a very well controlled fluid mechanical environment. A versatile flow-bioreactor system (FBS) has been designed and developed in our group to serve this and other purpose(s) and it allows EC to be subjected to a combination of mechanical stimuli. The FBS is capable of reproducing the flow waveforms at different locations of interest in the vasculature (Figure 5.1.5a) and hence can be used to subject cultured EC to physiological levels of mechanical forces, individually or in combination. The pressure range can also be adjusted to the desired physiologically normal or hypo/hypertensive levels (Figure 5.1.5b). The shear stress applied to the EC by the FBS has been modeled using detailed computational fluid dynamics (CFD) and a map showing variations in shear stress over the area where
the cells are cultured (Figure 5.1.5c) can be extracted and used predict these stresses and to ensure that the EC cultured in the system are subjected to well-defined and quantified mechanical forces (Figures 5.1.5d, 5.1.5e). In parallel to this, we have developed a dedicated automated image processing/segmentation programme which is being used to aid the analysis of EC response to mechanical stimulation (Figure 5.1.5e). This system not only allows us to perform experiments to better understand the effects of different mechanical stimuli in the development of atherosclerosis, its modular design and simple set-up allows easy incorporation of further modifications for extending its applications and the range of experiments which can be performed. These modifications include incorporating a library of atheroprone and atheroprotective shear stress profiles, culturing EC in monolayer or co-culture with smooth muscle cells (and fibroblasts) on flexible substrates, or excised tissues, and subjected to physiological cyclic stretch and circumferential deformation to the cells to understand their interactions, in normal and pathological events, while it also allows for mechanical stimulation of vascular cells for engineering vascular tissues. It is also expected to be useful in anastomotic engineering, design of vascular devices e.g. stents, understanding cells and biomaterials interactions, as well as developing vascular disease models, angiogenesis and vascular networks formation. In the future, we aim towards developing a flow-bioreactor system with feedback control/auto-regulation and with capabilities for live cells imaging and continuous online monitoring and assessment of cell profile as well as mechanical/structural properties/profiles of engineered vascular tissues/network.
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d e f
Figure 5.1.5. (a) Comparing requested physiological flow waveforms and those reproduced by FBS. (b) Some examples of physiologically normal or hypo/hypertensive pressure waveforms obtained in the FBS. (c) Map of WSS showing distributions within ±1% to ±5%. (d) Morphology of EC cultured under static condition for 13 hours. (e) Morphology of EC cultured under steady flow condition in FBS for 13 hours. (f) Image of mmunostained EC segmented to extract cell number, aspect ratio, cell alignment, nucleus, centroid.
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iomaterials and Tissue Engineering
Spectroscopic analysis for clinical diagnosis and monitoring of cancerCancer is the 2nd highest cause of death worldwide, and despite impressive advances in treatment, there are still a lack of diagnostic and prognostic markers. We are entering an age of extensive data on cancer where the challenge now is to assign clinical relevance to this data for diagnostic and particularly treatment purposes.
Recent technical advances in vibrational spectroscopy of biological molecules can generate spectral data on cancer tissues samples, where a chemical structural image (Figure 5.1.6) of the complex biological tissue is obtained using Infrared and Raman Spectroscopies.
Figure 5.1.6. Infrared image of cancer tissue with associate spectroscopic analysis.
In recent research from Ihtesham ur Rehman and colleagues (Sheila MacNeil, Rob Coleman, Martin Thornhill, Jonathan Bury, Helen Coley and Ingunn Holen), we are developing a spectroscopic process that can help in precisely identifying the chemical structural differences between the normal and cancerous cells an in addition differentiating the sub type of cancers.
Raman spectroscopic chemical imaging is employed for tissue (normal and cancerous) sample analysis, focusing on key criteria that need to be considered in clinical diagnosis including resolution, accuracy, robustness, speed, cost and how easy it is to use. Advanced novel signal and image analysis techniques are employed to develop a decision support system that can provide quantitative assessment of every single pixel of a tissue, as well as a subsection of an image frame and a whole image frame on the degree of abnormality, with confidence levels of the assessment of between 97 to 99%. This involves investigation of multi-scale signal and image-processing methods using wavelets, multi-mode multivariate statistical control based on principal and independent component analysis, as well as genetic programming based tree classification.
Figure 5.1.7. PLS1- PLS-DA model applied to the training and test sets. The high-dimensional spectral space has been reduced to a two-dimensional space of PLS scores (T1 and T2); the classifier is shown as the dashed line.
Figure 5.1.8. FTIR and Raman spectra of Normal, DCIS (HNG), and IDC (GIII) Breast Tissues.
Raman and FTIR spectra of the normal breast tissue were compared with malignant tissue. Different grades of ductal carcinoma in situ (DCIS) and invasive ductal carcinoma (IDC) were analysed with the aim to evaluate precisely how spectroscopy could differentiate between these grades and any biochemical changes taking place.
The research work on breast cancer tissue samples to develop an approach of early diagnosis of various histopathological subtypes and monitoring changes in response to treatment is continuing. Another project is focusing on differentiating between benign moles and metastatic melanoma employing well developed in-vitro models (by Sheila MacNeil) which in turn will help with early, non-invasive detection of metastatic melanoma. We are also working on analysis of oral squamous cell carcinoma, the commonest cause of head and neck cancer (in collaboration with Martin Thornhill) in an attempt to develop an early and non-invasive diagnostic technique using recently developed a 3D tissue-engineered human models that accurately replicate normal oral mucosa, dysplastic epithelium and invasive Oral squamous cell carcinoma (OSCC). OSCC, a primary cause of HNC, evolves from normal epithelium through mild, moderate and severe dysplasia to carcinoma in-situ before invading into the connective tissue to form carcinoma.
We believe that this work will ultimately expand to incorporate all cancers, and not only cancer, other diseases as well. We believe exploitation of this data has the potential to revolutionise clinical medicine and fulfil the promise of the “spectroscopy of biological molecules era” to impact positively on human health.
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Laser Fabrication of Tissue Engineering ScaffoldsThe work carried out in Fred Claeyssens’ research group focuses on laser fabrication of 3 dimensional constructs for tissue engineering. To achieve this we scan a laser through liquid photocurable biocompatible materials (poly-ethylene glycol, polycaprolactone, polylactide or poly-trimethylene carbonate). The laser irradiated material solidifies, and via xyz-scanning we can build up a 3D microstructured material directly from a computer file via Computer-aided-Design/Manufacturing (CAD/CAM). In our group we are utilising standard stereolithographic processes, where objects are build in a layer-by-layer fashion with, at best, 10 µm resolution. Additionally we are developing processes based on 2-photon polymerisation where we can achieve a much higher resolution (~100 nm). We specifically utilise these laser-based technologies for constructing scaffolds for tissue engineering applications as highlighted in the following examples:
Corneal tissue engineering: development of a microfabricated artificial limbus with artificial stem cell niches for corneal repairThis project focuses on the development of an artificial limbus incorporating stem cell niches. These niches act as well-defined microenvironments for limbal stem cells development and protection. In accidents or diseases where the surface of the cornea is damaged, stem cells are crucial for corneal regeneration. These corneal problems caused by chemical burns, Aniridia or Steven Johnson syndrome can result in the formation of scar tissue over the cornea and lead to permanent blindness. Providing synthetic microenvironments for limbal stem cells is a novel approach which is envisaged to aid in the regeneration process. In this project Sheila MacNeil and co-workers build artificial microenvironments or niches via microstereolithography (microSL) to mimic the structure of the natural stem cell niches. MicroSL allows the building up of user-defined structures via a layer-by-layer photocuring of the material. Photocurable polymers such as polyethylene glycol diacrylate (PEGDA) are used in this application due to their well-known properties for tissue engineering applications and biomedical uses. We have been able to build different prototypes of limbal rings incorporating stem cell niches (Figure 5.1.9), and we have been able to selectively tune the surface chemistry of the stem cell niches (Figure 5.1.9). We are currently studying these rings in a rabbit corneal organ culture (Figure 5.1.9) to assess the efficiency of these scaffolds for corneal tissue engineering.
Figure 5.1.9. (left) photograph of a corneal tissue engineering scaffold, (middle) scanning electron micrograph highlighting a stem cell niche incorporated within this scaffold and (right) scaffold incorporated in a rabbit corneal organ culture.
Neural Tissue Engineering: direct laser writing of 3D scaffolds for neural tissue engineering applicationsJohn Haycock and co-workers have produced high-resolution 3D structures of polylactide-based materials via multi-photon polymerization and explores their use as neural tissue engineering scaffolds. To achieve this, a liquid polylactide resin was synthesized in house and rendered photocurable via attaching methacrylate groups to the hydroxyl end groups of the small molecular weight prepolymer. This resin cures easily under UV-irradiation, using a mercury lamp, and under femtosecond IR irradiation. The results showed that the photocurable polylactide (PLA) resin can be readily structured via Direct Laser Write (DLW) with a femtosecond Ti:sapphire laser and submicrometer structures can be produced (Figure 5.1.10). The maximum resolution achieved is 800 nm. Neuroblastoma cells were grown on thin films of the cured PLA material, and cell viability and proliferation assays revealed good biocompatibility of the material. Additionally, PC12 and NG108-15 neuroblastoma growth on bespoke scaffolds was studied in more detail to assess potential applications for neuronal implants of this material. The study revealed that the PLA-based photocurable resin supports well neuronal cell growth and that these structures can be used to study aligned cell growth (Figure 5.1.10) and cell ingrowth in scaffolds.
Figure 5.1.10. (left) Detail of a Direct Laser Written scaffold and (middle and right) NG108-15 neuronal cell growth on a line pattern of PLA.
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5.2 Functional Materials and DevicesRare Earth doping of BaTiO3: a combined study by experimentation and atomistic simulations Trivalent rare earth (RE) ions are commonly used to modify the electrical properties of ferroelectric perovskite BaTiO3 (ABO3) ceramics in applications such as multi-layer ceramic capacitors (MLCC’s) and positive temperature coefficient of resistance (ptcr) thermistors. Due to the intermediate size and charge of the RE3+ ions compared to the Ba2+and Ti4+ ions, at least five different aliovalent doping mechanisms (ionic and electronic) are plausible. In many cases, the doping mechanism(s) are dependent on processing parameters such as the oxygen partial pressure (pO2), sintering temperature/time and overall A/B ratio in the formulation of the device. The situation is further complicated as commercial devices are heterogeneous and deliberately prepared under non equilibrium conditions to optimise/control the desired electrical properties. For example, short sintering times are employed in MLCC’s to ensure limited diffusion of dopants such as RE3+ ions into the grains to create so-called grain core-shell microstructures that are required to modify the temperature dependence of the permittivity and therefore capacitance of the device. In the case of semiconducting ptcr-BaTiO3 thermistors, low levels (<< 1 at%) of RE3+ doping occurs on the A-site and devices are cooled from the sintering temperature to allow limited (but necessary) up-take of oxygen along the grain boundaries to create and/or enhance the Schottky barriers between the semiconducting grain-insulating grain boundary junctions required to create such a non-ohmic device. All of these issues ensure the defect chemistry of RE-doped BaTiO3 to be an important but complex topic.
A-site doping of RE3+ ions has been a challenging topic for many years with the room temperature dc resistivity of ceramics being either semiconducting or insulating depending on the level of dopant and/or the ceramic processing conditions. The resistivity decreases by > 8 orders of magnitude with low levels of doping (<< 1 at%) to yield semiconducting ceramics; however, the resistivity becomes insulating with higher doping levels. A popular interpretation of this result for RE = La based on dc conductivity experiments of ceramics and atomistic simulations reported in the mid 1980’s is that there is a switch in the doping mechanism with increasing doping level. At low dopant levels an electronic (possibly donor doping) mechanism occurs to induce the semiconductivity but there is a switch to an ionic compensation mechanism at higher doping levels to re-establish the insulating behaviour. In recent years, Nahum Maso, Yang Liu, Derek Sinclair and Tony West have questioned this interpretation and in particular, the need for a ‘magic switch’ in the doping mechanism.
In this study Colin Freeman, John Harding and Derrick Sinclair have presented a new set of interatomic potentials for modelling BaTiO3 that includes covalency associated with the Ti-O bonding (Freeman, Dawson, Chen, Harding, Ben and Sinclair, J Materials Chemistry 21, (2011) 4861-68. The potential model is fitted using multiple parameters to a range of experimental and
ab initio data including the cohesive energy and lattice parameters of BaTiO3, BaO and rutile TiO2. This procedure provides internal consistency to the potential model for studying the energetics of the defect chemistry of BaTiO3. This is tested by examining trivalent rare-earth cation doping in BaTiO3 and considering all possible compensation (doping) schemes. Our simulations are in agreement with experiment and predict small rare-earth cations to dope exclusively on the Ti site (so-called acceptor doping), see Figure 5.2.1(a); medium sized rare-earth cations to dope on both the Ti and Ba sites and large rare-earth cation doping (eg La) exclusively on the Ba-site. For Ba-site substitution the simulations predict electron compensation (so called donor-doping) to be energetically unfavourable compared to the formation of Ti vacancies, i.e. Ba1-xRExTi1-x/4O3, see Figure 5.2.1(b). The apparent disagreement with electrical conduction of these ionic doped compositions is explained by subsequent Oxygen-loss which leads to the creation of Ti3+ cations, i.e. Ba1-xRExTi1-x/4O3- where = oxygen loss. Our simulations show that oxygen-loss is much more favourable in the ionic-doped system than pure BaTiO3 due to the unique local structure created around the defect site, see Figure 5.2.1(b). These findings resolve the so-called ‘donor-doping’ anomaly in BaTiO3. There is no need to invoke a magic switch in doping mechanism and our results explain the source of semiconductivity in positive temperature coefficient of resistance (ptcr) BaTiO3 thermistors.
We have also developed a potential model for the hexagonal polymorph of BaTiO3 (Dawson, Freeman, Ben, Harding, and Sinclair, J Applied Physics, 109 (2011) 084102). Again, excellent agreement with experimental results on the defect chemistry has been obtained. These studies show the power of combined work between experimentalists and modellers in the Ceramics and Composites Laboratory (CCL) to unravel the defect chemistry of complex but important electroceramics.
Figure 5.2.1. Lowest binding energy defect clusters for (a) B-site (acceptor doping) BaTi1-xRExO3-x/2 with the creation of oxygen vacancies and (b) A-site doping Ba1-xRExTi1-x/4O3 with the creation of B-site vacancies. Code: oxygen red, barium green, rare earth (RE3+) blue, titanium vacancy silver.
A new generation of pyrochlored-structured tunable dielectricsThe majority of tunable device applications such as phase shifters, filters, tunable mixers and delay lines are based on varactors, ferrites and micro-systems but ferroelectrics and dielectrics provide promising alternatives to reduce insertion losses associated with semiconductors and device fabrication difficulties and frequency limitations in ferrites. Devices operate by applying a large bias field (0.5MV/cm) to thin dielectric films which suppresses the permittivity and changes its resonant frequency. The main factors dictating materials selection for ferroelectric/dielectric phase shifters and filters include high relative tunability, (Cmin-Cmax)/Cmin,
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where Cmax and Cmin are the capacitances at the maximum and minimum dc bias fields, low insertion losses at the operating frequency and range of dc biases, moderate relative permittivity (r < 500, depending on applications) to enable device impedance matching and a crack-free, smooth surface morphology.
Figure 5.2.2. Three-dimensional atomic force micrographs of the typical as-deposited film along with the post-annealing films of various compositions, illustrating their relative root mean square (r.m.s.) surface roughness.
In 2001, research at Sheffield by Ian Reaney demonstrated that Pb1.5Nb2O6.5 had ultra low dielectric loss (0.0002) and a high r (260) which suggested that compositions based on PbO-Nb2O5 were potential candidates for tunable dielectrics. In a collaborative study, Ian Reaney with Brian Hayden of Southampton University have developed a new generation of tunable dielectric thin films using a high throughput combinatorial approach. A range of PbO-Nb2O5 thin compositions, Figure 5.2.2, were deposited using a bespoke Physical Vapour Deposition technique on a single chip and the dielectric properties and tunabilities measured. The tunability peaked in the cubic pyrochlore phase at ~37%Pb, Figure 5.2.3. These compositions have the best combination of tunability (26%), low dielectric loss (0.0009) and high permittivity (420) discovered to date and have great potential for the fabrication of tunable electronic devices which can be used to modify the filtering frequency of circuits.
Figure 5.2.3. Dielectric tunability versus dc bias field and composition measured at 10 kHz and -60 °C.
Simple cubic packing of gold nanoparticles by self-assemblyNanoparticles functionalized with liquid crystal forming molecules exhibiting self–assembling properties are currently receiving increasing attention due to recent theoretical studies suggesting that such systems could provide the base for metamaterials. Metamaterials display interesting properties, including negative refractive index,
that can potentially make things invisible when “cloaked”. This is in contrast to earlier work on metamaterials which focused on top-down (lithographic) methods.
In an attempt to control the self-assembly of gold nanoparticles (GNP) into ordered arrays, the Goran Ungar and Xiangbing Zeng set out to place them into the center of a soft dendritic (tree-like) corona of controllable radial density profile (Kanie et al, J Am Chem Soc, 134, 808, 2012). It has been shown previously that RDP is the key determinant of the type of packing adopted by spherical supramolecular dendrimers (Ungar et al, Science, 299, 1208, 2003). As shown in Figure 5.2.4b, each GNP is covered with a double-shell corona. In the inner shell are alkylthiols, some of which are end functionalized with –COOH groups. The outer shell is formed by subsequent attachment of dendrons to those groups. By adjusting the number and type of dendrons, precise control of the RDP can be achieved. With the help of grazing incidence small angle X-ray scattering on oriented thin films, the formation of a highly ordered simple cubic lattice of self-assembled GNPs is established. This is the first simple cubic liquid crystal, thermo- or lyotropic, and is the first example of SC self-assembly in spherical NPs.
Figure 5.2.4. (a) 3D electron density map of a unit cell of the simple cubic phase of gold nanoparticles coated with an organic double shell of hydrocarbon chains (inner) and dendrimer (outer). Isoelectron surface delimits the spherical region of highest density, i.e. gold; organic matter fills the continuum. (b) Schematic of a part of a GNP surface with double corona. (c) (110) section through the unit cell.
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Furthermore, a 2D hexagonal superlattice is also found, made up of dense and sparse strings of nanoparticles, as shown by the electron density map in Figure 5.2.5a. For every two densely packed column there is a diluted one, containing half the number of NP (Figure 5.2.5b). Further studies utilizing quantum dots and magnetic NPs are now in progress.
Figure 5.2.5. The superlattice of hexagonally arranged dense and sparsely populated columns of gold nanoparticles coated with a paraffinic-dendritic double corona. (a) 2D electron density map. (b) 3D model.
Complex patterns in liquid crystalsIn a recent publication the Goran Ungar and Xiangbing Zeng, a new way of making small molecules self-assemble into highly complex nanopatterns has been established that will help expand the capabilities of nanopatterning for advanced functional materials (Zeng et al, Science, 331, 1302, 2011).
T-shaped molecules consisting of a rigid rod aromatic core capped at each end with hydrogen-bonding groups and having a flexible non-polar side chain, have been found to assemble in honeycombs with cells of different polygonal cross-sections (Ungar et al, Adv Funct Mater, 21, 1296, 2011), from triangular, square, through pentagonal, hexagonal and beyond (Figure 5.2.6a-c). If a second chain is attached to the opposite side of the rod, an X-shaped molecule results (Figure 5.2.6d). Moreover, if that second chain is incompatible with the first, we could obtain honeycombs described as two-colour tilings. Two examples are shown in Figures 1e,f (Glettner et al, Angew Chem Int Ed, 47, 9063, 2008).
If the chain volumes are too large for triangular yet too small for square cells then regular structure formation can be highly frustrated, resulting in LC honeycombs with highly complex self-assembled “multicolour tiling” patterns. Thin films were studied by grazing incidence small-angle X-ray scattering (GISAXS). Figures. 5.2.7a,b show GISAXS patterns of two such “multicolour” honeycomb phases. Although the molecules are small (ca 3 nm), the unit cells are large: 21 x 11 nm for the high-temperature phase. Reconstructed electron density maps (Figures 5.2.7c,f) reveal that in neither of the two phases is a clean separation between the two types of chains possible. In the low-temperature phase the honeycomb is composed of three types of tiles, each of a different composition (colour): triangles, rhombuses and squares (Figure 5.2.7e).
Even more complex is the high-temperature phase. This honeycomb contains 18 channels in a unit cell. They are of five different colours (compositions) and four different shapes, shown in Figure 5.2.7h. The elipses in
Figures 5.2.7f,g hint that it is likely that a phase with the “forbidden” 12-fold rotational symmetry may be found soon in these systems. This would be the first example of a honeycomb quasicrystal. We note that quasicrystals have won D Schechtman the Nobel Prize for 2011.
Figure 5.2.6. (a) T-shaped molecules and (b,c)“single-colour” LC honeycombs. (d) X-shaped “tetraphiles” and (e,f) “two-colour” honeycombs.
Figure 5.2.7. (a,b) GISAXS patterns of a thin film of an X-shaped LC compound in the low- and high-temperature phases. (c,f) Corresponding electron density maps (purple high, red low), with schematic molecules partly superposed (red and green side-groups are carbosilane and perfluoroalkyl chains). (d,g) Representation of the honeycombs as tilings. (e,h) Tile types constituting the two phases and their number in a unit cell.
Axial-bundle phases - new modes of 2D, 3D, and helical columnar liquid crystalsLiquid crystals have transformed our daily lives, with the LCD industry currently being worth £300 B per year worldwide. The nematic phase, the most common LC phase used in displays, is formed by rod-like aromatic molecules bearing a flexible chain at one or both ends. In recent years a new type of LC molecules gained prominence, having flexible chains attached to the side rather than the ends. Such T-shaped molecules were
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found to form honeycomb structures e.g. as shown in Fig. 5.2.8(a,b). An increase in side chain volume, e.g. by attaching two instead of one side chain, honeycombs give way to layered structures (Figure 5.2.8(c)). In a recent study by the Goran Ungar and Xiangbing Zeng (Prehm, Liu, Zeng, Ungar and Tschierske, J Am Chem Soc, 133, 4906, 2011), the linear side-chains were replaced with branched “swallow-tail” ones (Figures 5.2.8d and 2a). Interestingly, such compounds exhibit the hexagonal columnar phase again. However, this time the structure is an inverted honeycomb, with the columns having a hard aromatic core and a soft aliphatic sheath. Unlike the classical discotic columnar phases, the new phase is made up of bundles of around 10 rod-like molecules in cross-section, with the rods aligned parallel to the column (Figure 5.2.8d).
At high temperatures the rod-like molecules are distributed evenly along the column length. At lower temperatures they gradually group together forming periodic modulation of the columns, as clearly seen in the electron density map in Figure 5.2.9b (pink). In fact the structure changes from 2D periodic to 3D periodic, with the columns shifted by 1/3 of a molecule longitudinally relative to their neighbours. This is coupled with segregation of the two branches of the swallow tails – one being an aliphatic hydrocarbon, the other fluorinated Teflon-like (RF in Figure 5.2.9a). The fluorinated regions are found to condense into right- and left-handed helices (Figure 5.2.9c).
This work opens the way to creating novel nanopatterned organic semiconductors, and illustrates the fact that there is much more yet to be discovered in liquid crystals. There has been a flurry of discoveries of new and ever more complex structures with great promise of new nanomaterials for optics and molecular electronics, photovoltaic, LED, ceramics templating and other applications.
Figure 5.2.8. Representative LC structures in T-shaped molecules with increasing volume of the side chains. Blue: hydrogen-bonding groups; grey: rod-like cores; green: laterally attached chains.
Figure 5.2.9. (a) The compounds. (b) 3D electron density map of the rhombohedral phase: blue-purple are regions of highest density (fluoroalkyl), pink are regions of low density, i.e. the aromatic bundles. (c) Schematic representation showing RF helices, green: RF regions, grey: aromatic.
Stretched Hexagonal
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5.3 Nuclear EngineeringThe safe disposal of spent nuclear fuelInternationally, deep geological disposal of spent nuclear fuel is currently accepted as the best available approach. Public acceptance of geological disposal will depend critically on the scientific credibility and transparency of the supporting disposal system safety case. Our research in this area, lead by Neil Hyatt and Claire Corkhill, is focussed on resolving key uncertainties associated with spent fuel dissolution mechanism(s), eliminating arbitrary conservative assumptions, and thereby ultimately reducing the overall cost of disposal. We are primarily working with the Finnish and Swedish implementation authorities, with support from the EU REDUPP project. In collaboration with groups at Stockholm and Macquarie universities, we have successfully fabricated sintered CaF2 ceramics with a microstructure similar to that of pristine UO2 fuel (also with the fluorite structure). The higher reactivity of CaF2 (as a UO2 analogue) permitted investigation of the dissolution behaviour at room temperature in real time using confocal optical profilometry. Comparison of the microstructure of the pristine material (A), with that of samples dissolved for 36h (B), and 276 h (C), showed the presence of both grain boundary and etch pit dissolution features at early reaction times, and the development of crystallographically faceted etch pits at later dissolution times. Furthermore, we were able to demonstrate the development of surface roughness and dissolution rate to be sensitive to the crystallographic orientation of sintered grains, based on supporting EBSD measurements. The importance of this research is the successful development and demonstration of a methodology to characterise the contribution of grain boundaries and etch pits (associated with surface terminated dislocations) to the overall mechanism and extent of spent fuel dissolution (Godinho, Piazolo, Stennett andHyatt, Journal of Nuclear Materials, 419, 46-51 (2011)).
Figure 5.3.1. Optical profilometry of CaF2 alteration.
An alternative disposal scheme for higher burn-up spent fuels Co-disposal (along with ILW) in a mined, engineered repository is problematic for spent fuels due to the high heat output, particularly at higher burn-up (55 -65 GWD/tonne), requiring extended periods of pre-disposal cooling and lower container loadings. A less temperature sensitive option involves disposal of spent fuel in very deep geological boreholes. Karl Travis and Fergus Gibb have developed a version of the deep borehole disposal (DBD) scheme for the consolidated disposal of spent fuel at burn-ups relevant to those expected Gen III reactors.
The basic idea is of DBD involves the construction of large diameter holes (~0.5m) in diameter drilled to a depth of > 4 km into a suitable host rock (usually the granitic basement of the continental crust), with waste packages emplaced in the bottom 1 km of the hole. DBD takes advantage of a geological barrier that is an order of magnitude greater than that of a standard repository, utilizes the very low hydraulic conductivities found at these depths and benefits from the chemical and physical isolation (over millennia) of intrarock fluids from near surface mobile groundwaters resulting from density stratification (see Figure 5.3.2).
Figure 5.3.2. Diagram showing relationship between a deep geological borehole and local geology.
Using numerical computation (finite differences) we have solved the heat conduction equation and determined temporal and spatial dependence of the temperature for a wide variety of disposal scenarios. These calculations have established that disposal of higher burn-up spent fuel by DBD is feasible. Furthermore, they have enabled us to explore a wide area of the parameter space which includes: the number of fuel pins per container, age and type of the waste, and number of containers per borehole. Our results have enabled the construction of a “phase field” diagram (see figure 5.3.3) which can be used to determine the best support matrix to use down-hole – either a special lead alloy or geothermal grout. The criteria upon which this is based is the maximum temperature reached on the surface of the waste containers, whether this exceeds the liquidus of the lead alloy and the time taken to reach this temperature. For spent MOX at 65 GWD/t shown in the figure, our results suggest that most combination of pin number and age are compatible with the preferred support matrix (lead alloy). Plots such as these are significant as they allow manipulation of the parameters to achieve a desired outcome. Our work on DBD is recognised as internationally leading and we are currently part of a consortium involving Sandia National Labs and MIT looking to develop a version of DBD for disposal of US spent fuel.
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Figure 5.3.3. Engineering field diagram for spent MOX at 65 GWD/t burnup.
Rapid synthesis of Pb5(VO4)3I by microwave dielectric heatingThe immobilisation of iodine radioisotopes is of interest from the viewpoint of advanced nuclear fuel cycles, potential future limitations on discharge practices, and the emergency response to nuclear accidents. In this respect, a leading candidate wasteform is the lead iodovanadinite, Pb5(VO4)3I, which adopts an apatite structure in which the iodide anions are contained within one-dimensional channels. A key issue with solid state synthesis of this material is the volatility of iodine at high temperature, necessitating the use of a closed reaction system or over pressure. Recognising the high dielectric loss of V2O5 at domestic microwave frequency (2.45 GHz), Neil Hyatt and Martin Stennett successfully demonstrated the synthesis of Pb5(VO4)3I in only 3 minutes at ambient pressure in an open container. Complete retention of the iodine inventory was achieved as a consequence of both the inverse temperature profile characteristic of microwave dielectric heating and the fact that the Pb5(VO4)3I product is not an efficient microwave absorber, thus effectively decoupling the sample from the heat source on completion of the reaction. This approach produced, for the first time, fully stochiometric Pb5(VO4)3I, without iodine vacancies, the structure of which we determined by Rietveld analysis of powder X-ray diffraction data (Stennett, Pinnock and Hyatt, Journal of Nuclear Materials, 414, 352-359 (2011)). Following the incident at the Fukushima Dai-ici site in March 2011, the potential application of this research to immobilisation of iodine radioisotopes released a nuclear reactor accident was highlighted in several media articles, see, for example, Bland, Materials Today, 14, 7–8 (2011).
Figure 5.3.4. The crystal structure of stoichiometric Pb5(VO4)3I prepared by microwave heating.
Development of novel magnesium cement wasteformsRadioactive waste streams that include metallic uranium are generally incompatible with conventional ordinary Portland cement (OPC)-based encapsulation matrices, as a consequence of hydrogen production resulting from interaction with the hyperalkaline environment of the cement. Adrian Covill and Neil Hyatt have investigated the formulation of a potential alternative magnesium phosphate systems for the encapsulation of such problematic waste streams. When compared to conventional OPC based systems, our magnesium phosphate formulations exhibit lower pH, and are able to chemically combine more mix water into the system to provide sufficient workability at water/solid ratios close to the confines needed for paste saturation. Importantly, our work has established the compliance of this alternative cement system material against NDA RWMD guidelines for strength and expansion, supporting the future deployment of this methodology. This research was carried out in collaboration with Amec Nuclear UK and was published as Covill, Hyatt, Hill and Collier, Advances in Applied Ceramics, 110 151-156 (2011).
Figure 5.3.5. Compression strength of novel magnesium phosphate cement formulations.
Radiation damage in ceramics for actinide immobilisationThe rate and impact of the crystalline – amorphous phase transition in actinide doped ceramics is a key uncertainty in the long term performance of these materials. We have approached the investigation of this issue using the implantation of energetic ions (e.g. 2 MeV Kr+) to simulate the ballistic cascade triggered by the -recoil daughter, forming a thin surface amorphised layer on polycrystalline ceramics. Daniel Reid, Martin Stennett, Amy Gandy and Neil Hyatt have developed a new grazing angle X-ray Absorption Spectroscopy method to investigate the structure of such radiation amorphised surface layers and, importantly, we have demonstrated from a study of ancient metamict mineral analogues that such structures are indistinguishable from those formed at naturally occurring dose rates. In collaboration with the group of Prof. Bill Lee at Imperial College London, we have successfully shown that Focussed Ion Beam milling may be applied to prepare cross-sectional TEM specimens from these materials. A highlight of this research is the observation of a mechanism of radiation
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damage healing in ion beam implanted perovskite, CaTiO3, which functions as an actinide host in the Synroc ceramic wasteform. Remarkably, this leads to a buried amorphous layer located between two recrystallised and partly damaged regions, as shown by electron diffraction. This work is clearly important in establishing and explaining the inherent radiation instability of titanate ceramics, with implications for materials selection in the context of actinide immobilisation (Reid et al, Nuclear Instruments and Methods in Physics Research B, 268, 1847-1852, (2010); Davoisne, Stennett, Hyatt, Peng, Jeynes and Lee, J Nuclear Materials, 415, 67-73 (2011); Gilbert, Davoisne, Stennett, Hyatt, Peng, Jeynes and Lee, J Nuclear Materials, 416, 221-224 (2011)).
Figure 5.3.6. Cross sectional TEM and electron diffraction analysis of buried amorphous zone in CaTiO3 .
Calcium aluminate phosphate cement for encapsulation of aluminium containing nuclear wastes Paul Swift, Claire Utton and Hajime Kinoshita have been developing calcium aluminate phosphate cement (CAP) systems as an alternative cementing system for the encapsulation of aluminium-containing wastes from the UK’s legacy radioactive waste, in collaboration with National Nuclear Laboratory. Through a series of investigations, a formulation envelope was developed to fulfill the processing requirements defined by industry. X-ray diffraction, thermogravimetric analysis, and scanning electron microscopy incorporating energy dispersive spectroscopy, were used to characterise the phase composition and microstructure of the CAP system, and the effect of a supplementary material (pulverised fuel ash) on the processing characteristics of various CAP systems i.e., setting time, fluidity, compressive strength, density and porosity. The potential for encapsulation of aluminium metal was assessed by encapsulating aluminium waste simulant in two CAP cementing systems and inspecting after 90 days curing and measuring the amount of hydrogen gas generated by corrosion of the encapsulated aluminium. The obtained results revealed that CAP systems was able to suppress the corrosion of aluminium specimens encapsulated and the hydrogen gas generation owing to the pH lower than conventional OPC systems, which demonstrated potential as an alternative cementing system for the encapsulation of aluminium metal.
Figure 5.3.7. pH of wet cement slurries of various cementing systems: CAP 1 and CAP2 have been developed at ISL.
Figure 5.3.8. Hydrogen gas generation over 7 days from aluminium encapsulated in various cementing systems.
Safe immobilisation of NROM wastes from oil industry. Significant radioactive contamination in the oil and gas industrial processes occurs due to the solid precipitates containing natural radioactive elements, commonly known as Naturally Occurring Radioactive Materials (NORM). The radioactivity in the precipitates primarily comes from radium and its daughter nuclides, which accumulates in the matrix of barium sulphate (BaSO4) scale due to the chemical similarity of radium and barium. Oday Hussein, Claire Utton and Hajime Kinoshita have been investigating safe immobilisation of such NORM wastes in cementitious matrices using BaSO4 surrogate. A series of experimental works have been conducted to investigate the effect of water content, BaSO4 particle size, and BaSO4 loading on fundamental properties of the OPC-BaSO4 system such as workability, setting time,
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phase formation, microstructure, porosity, compressive strength in order to optimize the wasteform formulation. The obtained results revealed that the particle size is the key factor to maximise the BaSO4 loading without a loss of integrity of wasteform in terms of microstructure and compressive strength. Both increase in water content and BaSO4 loading reduced the mechanical strength of the products causing the increase in porosity and suppression in formation of strong binding phases.
Figure 5.3.9. BSE image of OPC-BaSO4 system after 28 days of curing: granule 36 wt%, w/c = 0.53.
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5.4 Advanced Structural MaterialsNeural network modelling for diagnostics and control of plasma electrolytic processesEfficient process control is highly important in materials technology. In particular, coating processes must be carefully monitored in order to ensure surface characteristics and properties that determine overall material performance. One of the key issues in coating process control is to link unobservable surface properties (e.g. coating thickness and roughness) with observable and controllable process parameters. In plasma-based surface engineering processes, this is closely associated with the identification of electrical and optical characteristics of plasmas. Recent research carried out by Alexi Yerokhin at the RCSE in collaboration with the group of Dr Parfenov from Ufa State Aviation Technological University (Russia) (Parfenov et al, Automation and Advanced Technol, 4, (2011) 6-13; Parfenov et al Automation and Advanced Technol, 6, (2011) 7-15; Parfenov et al, Processes using Neural Networks, Neurocomputers: development and applications, 3, (2011) 47-56) has addressed the issue for the case of the Plasma Electrolytic Oxidation (PEO) coating process. It was proposed to use a combination of current characteristics and appearance of surface microdischarges that are a common feature of PEO for in-line process identification as the control object. Figure 5.4.1 illustrates developed identification methods that are based on the two-step neural network analysis which correlates process characteristics, such as applied voltage U and processing time t with surface layer thickness h and roughness Ra via analysis of instantaneous temporal distributions of microdischarge population NL(t) and apparent size SL(t). It is shown that general regression neural networks can provide up to 95% forecasting accuracy of the surface properties during the PEO process and are the most suitable network structures for this application.
Figure 5.4.1. Neural network approach for identification of Plasma Electrolytic Oxidation process.
Design and plasma synthesis of tribological surfaces for titanium alloysAlthough titanium alloys can carry high bulk stress levels, their wear behaviour is very poor. The substrate metal is also inherently very reactive under ambient, oxygenated conditions and, if the thin protective oxide film is removed by relative motion against a counterface material, accelerated wear ensues - with adhesive wear (and particularly galling and fretting) the dominant wear mechanism.
The Department’s Research Centre in Surface Engineering led by Allan Matthews along with Adrian Leyland is therefore developing plasma-based treatments for
titanium to improve the tribological performance. Previously, a wide variety of surface treatments (anodising, thermal, plasma, ion- beam, electron-beam, laser, etc.) have been studied and explored in the scientific literature. Generally, such studies have involved attempts to incorporate (small) interstitial species (i.e. O, N, C, B) into the near-surface, to provide combinations of i) solution strengthening ii) precipitation hardening and iii) surface ceramic compound layer formation. Processes receiving most research attention are thermal oxidation gas nitriding and plasma nitriding. At the commencement of our research, the challenges still to be addressed were (in oxidation treatments) build-up of high growth stresses in the oxide compound layer – with resulting stratification, brittleness and poor adhesion; and (in nitriding treatments) slow inward nitrogen diffusion – leading to a need for long treatment times at high temperature.
Our research has sought to overcome these drawbacks, whilst incorporating beneficial surface characteristics (such as an appropriate level of “in-plane” compressive residual stress to enhance fatigue performance). Processes investigated have included low voltage (LV) and high voltage (HV) ‘triode’ (ie. hot-filament enhanced) plasma nitriding (TPN), low then high voltage (LHV) TPN at high temperature (HT)and low- then high-voltage triode plasma oxy-nitriding (TPON) – where the nitriding treatment is preceded by an oxidation stage, to boost treatment depth. Our studies have shown that, as well as an appropriate diffusion case depth, thicker compound layers also contribute to the global compressive state – and that an oxygenated diffusion case although improving sliding wear performance, reduces the overall compressive stress effect.
Figure 5.4.2. Surface stresses for Ti-6Al-4v samples using XRD sin2ψ method (Cassar, Avelar-Batista Wilson, Banfield, Housden, Fenech, Matthews and Leyland, Int J Fatigue, 33 (2011) 1313-1323).
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The overall effectiveness of nitriding treatments (in terms of the hardness-depth profile) is improved by applying a low voltage for most of the process time (to prevent nitride compound layer growth from “blocking” nitrogen diffusion) and following this with a short high voltage stage (to introduce a compound layer at the end of the process – and take advantage of its superior hardness and wear characteristics).
Figigure 5.4.3. Hardness depth profile of Ti-6Al-4V sample diffusion treated for 4 hours (Cassar, Banfield, Avelar-Batista Wilson, Housden, Matthews and Leyland, Surf Coat Technol, 206 (2012) 2645-2654).
Figure 5.4.4. Log-Log (Basquin) plots of fatigue performance of (a) diffusion treated Ti-6Al-4V, and (b) diffusion treated and TiN coated Ti-6Al-4V (Cassar, Avelar-Batista Wilson, Banfield, Housden, Fenech, Matthews and Leyland, Int J Fatigue, 33 (2011) 1313-1323).
Low-to-moderate temperature (ie. ≤ 700°C) plasma-assisted diffusion treatments provide a significant improvement in fatigue behaviour. PVD TiN alone has a tendency to shorten fatigue life, but duplex TPN/TiN remains superior to the untreated (annealed) substrate material.
Figure 5.4.5. Critical loads for failure of 2.8 μm TiN coating deposited on LV-TPO and LBV-TPON treated Ti-6Al-4V (Cassar, Banfield, Avelar-Batista Wilson, Housden, Matthews and Leyland, Surf Coat Technol, 206 (2011) 395-404).
The “annealed” substrate provides a benchmark against which the various triode plasma treatments can be measured (ie. its bulk microstructure is similar to them). It is clear that the combined low- and high-voltage (LHV) nitriding treatment gives a major improvement in fatigue life (more so than low-voltage (LV) nitriding alone). Despite a larger overall treatment depth the high-temperature (HT) TPN and oxy-nitriding (TPON) treatments are less effective.
Triode plasma oxidation treatments provide more rapid diffusion case formation. However the oxide compound layer doesn’t favour the application of a subsequent PVD coating, since interfacial adhesion is poor (as assessed by the critical load for debonding in a controlled scratch test) – and the oxide layer is excessively brittle. However, a sequential oxidation + nitriding treatment can be used to remove the oxide layer and change the surface chemistry to improve the coating adhesion (and aid lubricant performance). The best results in this regard are obtained if the nitriding treatment duration is at least twice that of the prior oxidation treatment.
The process technologies described above have been used to take weight out of bearings used in Airbus aircraft.
Wear mechanisms in ceramic on ceramic hip prostheses
The use of alumina hip prostheses continues to grow (more than 3.5 million alumina components have now been implanted worldwide) as a longer life alternative to standard metal-on-polymer combinations, where life is often limited by osteolysis caused by the liberation of polymer wear particles. Explanted alumina on alumina hip prostheses frequently show a localised region of high wear, commonly known as “stripe wear” because of the characteristic shape. The stripe wear region is associated with high wear due to intergranular fracture, with a low wear region adjacent. While useful and important, the study of explanted joints suffers from uncertainty as the joints have experienced a wide range of differing operation conditions, including time in the patient, patient sex, weight, activity levels and so on. A more rigorous approach is to undertake in vitro testing where all test conditions can be carefully controlled. Peng Zeng, Beverley Inkson and Mark Rainforth, in collaboration with Todd Stewart (University of Leeds), undertook for the first time, a detailed transmission electron microscopy (TEM) study of the surface damage accumulation mechanisms following in vitro tested worn alumina hip replacement prostheses. TEM of focused ion beam (FIB) cross-section samples indicated extensive surface dislocation activity, which is perhaps surprising in a ceramic. Interestingly, the dislocation activity was restricted to the outer grain layer in all cases. Except for one example of basal slip, all slip was found to be on pyramidal planes. The dislocation activity was greatest in grains that exhibited intergranular fracture, suggesting that the small but important strain was responsible for initiating cracking, Fig. 5.4.6 and 5.4.7. The type, morphology and chemical activity of wear debris is critical to the life of a hip joint as wear debris migrates from joint into surrounding tissue which can then induce
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osteolysis and joint rejection. Three types of wear debris were seen from the worn surface, namely: granular wear debris, nanocrystalline wear debris and needle shaped wear debris. Wear debris was shown to arise from grain pull-out, severe plastic deformation at the surface and from a tribochemical reaction between the alumina and the calf bovine serum. The observations allow a mechanistic model of the damage accumulations leading to wear and ultimately failure in ceramic on ceramic hip joints (Zeng, Inkson, Stewart and Rainforth Acta Materialia, 60 2061–2072 (2012)).
Figure 5.4.6. (a) AFM image shows small (5-30 nm) height differences between grains on the worn surface; (b) Bright field TEM micrograph of a back-thinned samples of the worn surface showing an intergranular crack that runs between grains with a high dislocation density and low dislocation density.
Figure 5.4.7. Bright field TEM image of a FIB cross-section of the high wear stripe region showing intergranular cracking in the outer grains and an associated high dislocation density. The dark surface layer is a gold film used to label the original surface.
Eight fold increase in compressive strength of aluminium foam by use of a plasma electrolytic oxidation coatingIn the porous metals research group, work as been carried out looking at the effect of applying a Plasma Electrolytic Oxidation (PEO) coating to open celled aluminium foams. These materials already possess very good strength to weight ratios, and can be used as sandwich panel cores in lightweight structures, but this research seeks to boost these capabilities even further. It is well known that in foams deformation occurs by bending of the struts, and so if a stiff, strong phase can be introduced at the strut surface it should be a very efficient way of reinforcing it.
To attempt to achieve this PEO coatings have been applied to the foams by Taha Abdulla, Alexi Yerokhin and Russell Goodall; this is an electrochemical process that applies a large alternative voltage to a sample placed in an electrochemical bath. The microdischarge arcing events that occur result in the surface being transformed into oxides, and strong, well adhered coatings are regularly achieved on flat components. The foams are made in
the laboratory using the replication process, where liquid aluminium is forces between salt grains using gas pressure, with the salt grains being dissolved to leave behind a foam.
Different coating treatments produce different amounts of oxide, Figure 5.4.8, and have also been found to alter the structure and composition of the coating. The effect on mechanical properties has been assessed, and is found to be significant, Figure 5.4.9 demonstrates the results looking at the effect of frequency in the process, and it is seen that increases in the yield strength of up to a factor of 8 or so have been obtained. Of course, there is an increase in weight, but as shown in Figure 5.4.10, significant improvements in the specific strength are also possible.
Related research is currently examining how great an effect can be achieved through optimisation of the PEO process conditions for foams, and how to minimise the process time and costs. Also under investigation is how the composition and properties of the coatings vary with thickness, to understand why a thicker coating does not necessarily mean a better performance.
Figure 5.4.8. Alminium replicated foams with (left) no coating, and PEO processed using frequencies of 50, 250, 1250, and 6250 Hz respectively.
Figure 5.4.9. Stress-strain curves for foams with different PEO coatings tested in compression.
Figure 5.4.10. Log-log plot of yield stress against density for coated foam samples, with lines of equal specific strength marked. Even with the increase in weight, the increase in strength leads to overall favourable properties.
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Effect of strain path reversal on deformation induced ferrite transformationIn recent years, considerable focus has been given to methods to produce steels containing ultrafine grained (UFG) ferrite by relatively simple thermomechanical processing routes involving heavy deformation of the thermodynamically unstable austenite, i.e. below the Ae3 but above the Ar3 temperatures. It is generally believed that the formation of the UFG is assisted by the deformation induced ferrite transformation (DIFT). However, the transformation mechanism of the DIFT is still not fully understood. What is clear is that DIFT originates from the deformed austenite, and thus it is essential to understand the evolution of the deformation microstructure of austenite to determine the origin of DIFT.
Previous study conducted by Lin Sun, Krzysztof Muszka, Brad Wynne and Eric Palmiere revealed the effects of large strain and strain path reversal on the deformation microstructure evolution in austenite below the recrystallisation temperature using a non-transforming Fe-30wt%Ni model austenitic alloy (Sun, Muszka, Wynne and Palmiere, Scripta Materialia, 64 280-283 (2011)). Results show that the high angle boundaries (HABs) can be generated by both microstructure mechanism through dislocation accumulation and texture mechanism via subgrain rotation. However, multiple strain path reversals lead to less well-developed HABs in the original grains compared to single reversal deformed to the same amount of total accumulative strain. This effect is attributed to the subgrain rotation mechanism being less effective at small strains.
In current work, authors conducted the same hot torsion tests using a API X-70 microalloyed steel at a temperature between Ae3 and Ar3. A 2-pass test and an 8-pass test were conducted at the strain rate of 1s-1. The 2-pass test consisted of forward torsion to a von Mises equivalent strain of 1.0, then reverse torsion of εvm=1.0 to a total strain of 2.0 but a net strain of 0. The 8-pass test consisted of 4 cycles (8 passes) forward-reverse torsion with each pass a strain of εvm=0.25 producing the same total accumulative strain εvm=2.0 and a net strain of 0; however, achieved via a significantly different strain path compared to the 2-pass test. No interpass delay was allowed during testing therefore minimising any static ferrite transformation. After deformation, specimens were immediately water quenched to preserve the as-deformed microstructures. The cooling rates after the deformation to ambient temperatures were well beyond 150°C·s-1.
The microstructures of the X-70 steel after the 8-pass and 2-pass torsion-reverse torsion tests followed by immediate water quenching are shown in Figure 5.4.11 by secondary electron contrast and in Figure 5.4.12 for EBSD orientation maps. It can be seen that after the 2-pass test most of the austenite has already transformed to fine quasi-polygonal ferrite. As the cooling rate after the deformation is considerably fast (>150°C·s-1), it is believed that the majority of the ferrite was formed by the DIFT mechanism. Meanwhile, almost no DIFT ferrite was produced during the 8-pass test, therefore after quenching a microstructure of martensite was formed. These results indicate that although deformed
to the same total strain, multiple strain path reversal significantly retarded the DIFT mechanism. A very plausible explanation of this phenomenon can be drawn by comparison with the observed strain path effect on austenite grain subdivisions using the Fe-30wt%Ni model alloy in early study (Sun, Muszka, Wynne and Palmiere, Scripta Materialia, 64 280-283 (2011)). As the 2-pass test produced a large amount of HABs within the austenite grains, these boundaries could act as ferrite nucleation sites for DIFT. On the contrary, after the 8-pass test a very limited amount of HABs was produced by the texture mechanism. Without these intragranular nucleation sites for the ferrite, the onset of the DIFT process was significantly retarded.
Further examination on the misorientation distribution of the dislocation boundaries (shown in Figure 5.4.13) reveals the different phase transformation mechanisms taking place after the 8-pass and 2-pass tests. It can be seen that the density of HABs in the 2-pass deformed microstructure are much higher than that in the 8-pass deformed one. This is believed to come from the reconstructive phase transformation during DIFT process. DIFT is believed to be a reconstructive phase transformation involves diffusional nucleation and growth (Bhadeshia, Materials Science and Technology, 15 22-29(1999)) of the ferrite, therefore producing HABs with higher disorientation. Meanwhile, the displacvie transformation of the martensitic transformation experienced by the 8-pass deformed test does not involve any diffusion producing much lower levels of HABs.
Figure 5.4.11. SEM Microstructures of the X-70 steel showing significantly different extents of DIFT ferrite due to the effect of strain path reversal.
Figure 5.4.12. EBSD Microstructures of the X-70 steel showing significantly different extents of DIFT ferrite due to the effect of strain path reversal.
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ls Figure 5.4.13. The disorientation angle distribution of the HABs after 2-pass and 8-pass test as absolute frequencies per unit area (square mm).
Effect of strain reversal on microstructure and texture evolution of Ti-6Al-4V alloyIn primary hot working of Ti alloys, the breakdown of the as-cast large grain microstructure to a fine grain two-phase micro-structure (known as spheroidisation in Ti alloys) is an important technological process that leads to a highly formable micro-structure suitable for secondary hot working processes such as forging or superplastic forming. The process of breakdown of colony or basketwave alpha structure during subsequent hot working in alpha+beta phase field can occur dynamically (during deformation) or statically (after deformation). The mechanism of dynamic spheroidisation is believed to be the following: lateral interfaces form within the alpha lamellae as a result of the formation of shear bands or subgrain boundaries. The laths are subsequently broken up by interface-tension-driven beta phase penetration along the sub-boundaries/shear bands. Subsequently after annealing, coarsening processes such as Ostwald ripening take place and are believed to be the main reason of static spheroidisation. This processes are crucial for the room temperature properties of the final product (ductility, fracture-crack-initiation resistance) and is also strongly dependent on the applied strain path.
The effect of strain reversal on microstructure evolution and texture development in Ti-6Al-4V was studied in torsion by Krzysztof Muszka, Magdalena Lopez-Pedrosa, Brad Wynne and Matt Thomas. It was observed that strain reversal of 0.25 + 0.25 led to fully restored prior beta structure, whereas in the case of the same total strain applied in the monotonic deformation (Forward + Forward deformation route), the original beta structure was destroyed – Figure 5.4.14. It was also found that the non-monotonic types of deformation modes (reversed torsion) led to significantly slower spheroidisation kinetics compared to monotonic modes (monotonic torsion) – Figure 5.4.15. The proper assessment of the effect of strain path change on both dynamic and static spheroidisation is crucial from the prediction of the microstructure evolution point of view. A proper optimisation of the process routes for structural improvement can lead to a substantial cost reduction in widely used aplha+beta alloys and improvement of the properties of final products.
Figure 5.4.14. Inverse pole figure EBSD images of alpha grains (a,c) and reconstructed beta grains (b,d) for forward + forward and forward + reverse deformation.
Figure 5.4.15. Examples of basketweave (left) and spheroidised (right) microstructure in Ti-6Al-4V after deformation at 815 oC followed by 4 hours annealing. The graph shows the fraction of spheroidised grains as a function of annealing time.
The effect of shot peening on thermal stability of titanium alloysDue to their high specific strength and corrosion resistance, titanium alloys are an important class of engineering material for the aerospace, petrochemical, and more recently, the biomedical industries. To improve the fatigue and tribological properties, and their resistance to stress-corrosion cracking, titanium alloy components are often shot peened to work harden the surface layer and introduce a subsurface compressive residual stress that retards the growth of surface nucleated cracks. Whilst the beneficial effects of shot with respect to the compressive residual stresses peening have been well documented, microstructural characterisation of the subsurface deformation zones have received less attention. An improved understanding of such surface treatments, with particular respect to the microstructural response of the workpiece, will therefore provide an opportunity to engineer subsurface microstructures to optimize the localized mechanical properties of engineering components.
The response of the near-α titanium alloy Ti-834 to shot peening results in microstructural instability and enhanced brittle case formation following thermal exposure in air as shown by Meurig Thomas and Martin Jackson (Figure 5.4.16). The mechanical twinning from shot peening enhances the kinetics for oxygen diffusion at the surface of Ti-834 during high-temperature exposure, as illustrated in the oxygen diffusion profile in Figure 5.4.17. Therefore, the peening process increases alpha-
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case formation and subsequent surface embrittlement after prolonged exposure. The implications are that the benefits of the peening process which is designed to enhance surface mechanical properties, in particular fatigue resistance, could in fact be negated during thermal exposure, due to the increased propensity for oxygen enrichment and associated microcracking. Secondly, the fact that silicon comes out of solid solution within the highly deformed twinned region (Fig 5.4.16(b)), thus draining the primary alpha matrix of creep-enhancing silicon atoms, implies that there is a localized loss of creep strength near the surface.
The effect of workpiece temperatures; 77 K, 298 K and 553 K on the on subsurface microstructure and mechanical properties of CP-Ti is illustrated in figure 5.4.18. The corresponding microhardness data as a function of temperature are presented in figure 5.4.18d). At all temperatures investigated, peening leads to localised subsurface hardening, with the magnitude of hardening considerably greater than twice the standard deviation of the bulk hardness measurements. The degree of subsurface hardening increases commensurately with the temperature of the workpiece during shot peening, with both the depth of hardening and peak hardness being the least for the CP-Ti coupon that was shot peened at cryogenic temperatures.
The increase in subsurface hardening with higher peening temperatures can be explained by the interaction of dislocations with twin boundaries. There is strong evidence of strain hardening of CP-Ti due to deformation twinning, a result of both a reduction in effective slip length (Hall-Petch effect) and the conversion of glissile dislocations within the twinned volume into sessile dislocations as a result of the twinning shear transformation (i.e. the Basinski mechanism).
Figure 5.4.16. Backscatter electron micrographs of shot-peened Ti-834: (a) before thermal exposure, and (b) 973 K, 1800 h, showing the silicide precipitation along twin boundaries.
Figure 5.4.17. Oxygen content (normalized to wt.%) of as-machined and shot-peened (1200% coverage) Ti-834 exposed to air for 1800 h at 973 K. Data collected using secondary ion mass spectrometry (SIMS).
Figure 5.4.18. The effect of workpiece temperature on the microstructural response and subsurface mechanical properties of CP-Ti to shot peening. Cross-section polarized light micrographs of CP-Ti shot peened at 77, 298and 553 K are shown in (a)–(c), respectively (the direction of the shot stream is approximately vertical). Microhardness data and twin lineal fraction measurements are presented in (d).
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MultiscaleMaterials Modelling
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5.5 Multiscale Materials ModellingStress control of magnetic domain walls in patterned nanowiresJulian Dean, Matthew Bryan and Dan Allwood have proposed a new low power method of controlling the position of magnetic domain walls in patterned nanowires for data storage applications (Dean, Bryan, Schrefl and Allwood, J Appl Phys, 109, 023915 (2011)). We used finite element modelling to simulate a magnetostrictive (stress-sensitive) nanowire coupled to a piezoelectric substrate (Figure 5.4.1). The soft magnetic character of the nanowire creates a magnetic easy axis along the wire length. The wires are also able to support magnetic ‘domain walls’ across the wire width that separate oppositely oriented magnetic domains.
Figure 5.5.1. Simulated structure and calculated stress distribution.
Electric voltages applied to local contacts induce a stress distribution in the piezoelectric layer, which couples to the magnetostrictive wire. Our calculations showed how the stress gradients create energy minima and maxima for the position of domain walls that can be used to move and position domain walls (Figure 5.4.2). Domain walls can be passed between stable locations with very little energy (100s keV) on a nanosecond timescale. Alternate voltage configurations can be used to create a bistable “RAM” type operation (Figure 5.4.2) or sequential sequences can be used to propagate streams of domain walls for shift register type operation.
If successful, this development promises to overcome the existing challenges with magnetic nanowire technology of high power consumption and unreliable switching. We have also developed an analytical description of stress-control of domain walls in nanowires (Bryan, Dean and Allwood, Phys Rev B, in press). This analysis has shown that the axial strain gradients are responsible for domain wall motion in magnetostrictive nanowires.
Figure 5.5.2. Energy as a function of domain wall position for two voltage configurations and resulting minimum energy magnetic structures.
Finite element modelling of impedance spectroscopy As demand grows for the miniaturization of electrical components, the accurate characterisation of electro-ceramic materials becomes increasingly important. Impedance spectroscopy is much used for the analysis of the electrical properties of electro-ceramic materials. Traditionally, the spectra are analysed using an equivalent circuit. The finite element method (FEM) is a powerful tool widely used for the numerical modelling and simulation of many areas of physics and engineering. Julian Dean, Henry Foxhall, John Harding and Derek Sinclair use a FEM code developed here to simulate electroceramic materials using the time domain finite element method by solving Maxwell’s equations in time and space. This method allows for the comprehensive treatment of a full three dimensional granular representation of electroceramic materials and microstructure without the requirement for any equivalent circuit. This allows the complete microstructure of the system such as contacts, grain boundaries and grain cores to be analysed for the effects within the impedance spectrum. An example of the model and output is shown in Figure 5.5.3.
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Figure 5.5.3. (a) Simple voronoi model of a heterogeneous ceramic material with grain boundary. (b) and (c) show the calculated local electric field in the sample for high and low frequencies respectively corresponding to the excitement of the grain core and grain boundaries. (Red indicating a high region of electric field). (d) The simulated spectroscopic plot of Z* resulting from the differing time constants of the grain cores and grain boundaries.
Topological connectivity analysis of accumulated radiation damage from multiple molecular dynamics recoil cascadesAt present, it seems likely that much of the stored plutonium in the UK is destined for reuse as MOx fuel, but some will be unsuitable for this purpose and require immobilisation. The current waste management option for these arisings is a ceramic phase material based on the SYNROC C concept. Pyrochlore structures such as Gd2Ti 2O7 and Gd2Zr2O7 are of interest in radiation damage research. The phases have been shown to exist as stable metamict materials over geological timescales. Amorphisation occurs because many atoms are displaced in successive collision cascades. Simulations by Henry Foxhall, John Harding and Karl Travis of radiation damage are often analysed by identification of vacancy, interstitial and anti-site defects as a measure of damage. Topological connectivity analysis takes into account only connectivity, and so is suitable for crystalline, disordered or distorted material. Comparing Gd2Ti2O7 and Gd2Zr2O7 (see Figure 5.5.4) the former amorphises readily while the latter does not, forming a defective fluorite phase upon irradiation. We have used topological analysis to give a robust method of analysing for point defects. Zr-pyrochlore systems exhibited defect fluorite motifs upon radiation damage due to randomisation of oxygen ions over the anion sub-lattice. Ti-pyrochlores do not show this behaviour, with localised volumes of damage showing increased disorder, and primitive rings up to order-14. Both materials retain crystalline-type topological motifs.
Figure 5.5.4. Snapshots of the final configurations of the simulation, showing all atoms that have moved more than 1.0 Å from their initial positions (a) Gd2Ti2O7 (b) Gd2Zr2O7 .
Protein binding on calcite surfaces: simulations of ovocleidin-17 on calcite
Figure 5.5.5. Binding of ovocleidin-17 to a planar surface (left), acute steps (centre) and obtuse steps (right). Water is not shown for clarity.
Ovocleidin-17 has been identified as a protein involved in the formation of eggshells, although the role and function it performs is still not clear. Colin Freeman, John Harding and David Quigley and Mark Rodger (University of Warwick) have performed classical molecular dynamics simulations for the adsorption of the whole protein onto the {10.4} surface and also onto the acute and obtuse steps of calcite in several different configurations. The simulation show that binding is a competition between the protein and the strongly bound surface water. The protein is fairly rigid and the arginine residues are the most important binders to the calcite surface. The protein can bind to all three kinds of surface, but significant differences in the binding energy for the three surfaces were observed. This is likely to be due to the differences in water structure observed between the surfaces. However, this protein does not show the same degree of selectivity as found for other molecules such as the polysaccharides, which suggests that it is less likely to be involved in the control of crystal morphology. Previous simulations demonstrated that this protein can alter the energetic stability of the different phases of calcium carbonate, removing the barrier between amorphous calcium carbonate and the crystalline calcite phase. This implies that the protein may facilitate the crystallisation of calcium carbonate. These results do not suggest that it could function as a step binder to prevent the growing out of a face. This suggests that any function in crystallisation could be earlier in the growth process i.e. before large calcite planes are formed.
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Nanomaterialsand Nanoengineering
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5.6 Nanomaterials and NanoengineeringReal-time in-situ characterisation of friction and surface wear processesThe NanoLAB is pioneering in-situ dynamical analysis of friction and wear processes, having developed new technologies as part of the NanoLAB Basic Technology Nanorobotics programme. A novel triboprobe miniaturized to fit inside a TEM can cyclically rub a nanoscale surface over many thousands of cycles. This enables nanofriction and nanofatigue testing of individual nanostructures, with 3D control of the loading direction and simultaneous TEM imaging of the changing microstructure.
Using the NanoLAB TEM triboprobe the formation of nanoscale liquid droplets by friction of a solid has been observed in real-time by Beverley Inkson, Aiden Lockwood and Robert Milne. Dynamical imaging of the nanoscale cyclic rubbing of a focused-ion-beam (FIB) processed Al alloy by diamond shows that the generation of nanoscale wear particles is followed by a phase separation to form liquid Ga nanodroplets and liquid bridges. The transformation of a two-body system to a four-body solid–liquid system within the reciprocating wear track significantly alters the local dynamical friction and wear processes. Moving liquid bridges are observed in situ to play a key role at the sliding nanocontact, interacting strongly with the highly mobile nanoparticle debris. In situ imaging demonstrates that both static and moving liquid droplets exhibit asymmetric menisci due to nanoscale surface roughness. Nanodroplet kinetics are furthermore dependent on local frictional temperature, with solid-like surface nanofilaments forming on cooling. TEM nanotribology opens up new avenues for the real-time quantification of cyclic friction, wear and dynamic solid–liquid nanomechanics, which will have widespread applications in many areas of nanoscience and nanotechnology (Lockwood, Anantheshwara, Bobji, Inkson, Nanotechnology, 22,10 105703 (2011)).
Figure 5.6.1. Real-time imaging of the nanoscale liquid mechanics of Ga droplets.
Mechanics of nanoscale aluminiumThe mechanics of nanoscale structures is of great interest, since material in nanoscale volumes behaves differently from bulk. The size dependant deformation mechanisms of Al rods have been evaluated in real-time by uniaxial compression testing of Al nanopillars inside a transmission electron microscope. The compressive deformation mode of the Al pillars is observed to be dependent on the diameter/aspect ratio of the pillar under test. For comparable height pillars and increasing aspect ratio 2:1-6:1, the compressive deformation mode of the Al pillars changes from deformation via discrete
slip bands on multiple slip systems (aspect ratio ~2:1), to localized bulging at the apex of the pillar, followed by slip band initiation (aspect ratio ~4:1), to a full pillar buckling mode (aspect ratio ~6:1). Al pillar buckling is observed to initiate a new pillar deformation sequence, comprising lateral slip of the pillar, generation of a 90º pillar kink, and recrystallization. The dynamic recrystallization of the severely deformed Al changes the single crystal Al rod to a polycrystalline one (Milne, Lockwood, Inkson, J Phys D: Appl Phys, 44, 48 485301 (2011).
Figure 5.6.2. Real-time imaging of the compression of an aluminium single crystal to form new grains.
Electrical properties of individual magnetic multilayer nanowires Peng, Cullis, Luxmoore, Inkson, Nanotechnology, 22, 245709, (2011)
The basic electrical parameters of individual MNWs are intrinsically important and essential for their applications as functional building blocks and interconnecting leads in nanodevices and nanoelectronics. The transport properties of MNWs have mainly been reported by averaged measurements on arrays of MNWs, which are not precise for an individual nanowire. Furthermore, accurate and comprehensive electrical transport measurements on MNWs of known microstructure are necessary to further understanding of the origins of electrical resistance and giant magnetoresistance, and for designing novel functional multilayer structures for future industrial applications.
Here we report for the first time accurate and comprehensive measurements of electrical properties of individual CoPt/Pt multilayer nanowires both with periodic and non-periodic layer structures. A remarkably high failure current density of 1.7 × 1012 A m−2 has been measured. The resistance of both types of multilayer nanowire structures are well fitted by a series resistance model, determining the separate resistance contribution of the component layers and magnetic/nonmagnetic interfaces for a single multilayer nanowire. The field-dependent interface resistance of the CoPt – Pt interfaces lies in the range 4.8 -13.2 W , and the MNWs are observed to fail in-situ by thinning of the CoPt layers (Peng, Cullis, Luxmoore, Inkson, Nanotechnology, 22, 245709, (2011).
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Figure 5.6.3. Fabrication and electrical characterisation of 55nm diameter CoPt/Pt multilayer magnetic nanowires.
Ceria nanoparticle surface dynamicsUsing in-situ aberration corrected TEM imaging, it is nowadays possible to track the dynamical reconstructions occurring on nanoparticle surfaces with both high spatial and time resolution. In this work (Möbus, Saghi, Sayle, Bhatta, Stringfellow and Sayle, Advanced Functional Materials, 21(11) 1970 (2011)) the dynamics of ceria (CeO2) nanoparticles is explored by Guenter Möbus with particular attention to the mobility differences between {111} and {100} surface facets. Through electron irradiation, a variety of processes can be triggered in these oxide nanomaterials, including oxygen ablation, change of oxidation state of cerium, cerium surface reconstruction, and atomic hopping of cerium atoms along with changes in surface-near chemical bond lengths. The paper shows how to extract cation atomic number occupancy data from high-resolution phase contrast images with up to single atom precision. Using a series of 60 snap shots over 120s the time-evolution of a nanoparticle corner with {100} cap is tracked. The {100} surface is found highly mobile while neighbouring {111} facets remain immobile, which is evidence for polar dipole field mediated atomic rearrangements occurring exclusively on {100} type facets. Differing from electron beam ablation, the movements are found to be partially reversible and consist mostly of lateral displacements. However, at selected time steps, sudden relocation of multiple-atom columns is found. Further important experimental findings comprise significant changes of bond-lengths and deviations from crystallographic cerium positions in the terminating two monolayers, contributed by possible changes in cerium valence, oxygen deficiency, and the asymmetry of coordination at the surface.
The observations have been greatly facilitated by an exceptional electron-beam ablation of carbon support film, which allows background and noise-free observation of finest contrast details. The wide-ranging and fast carbon ablation is dependent on the materials loaded on the film and therefore a chemical rather than a straight beam drilling effect.
In collaboration with the theory group of D Sayle at Cranfield University, the experimental findings have been explained using molecular modelling and derivation of a charge-quenching model for the {100} surface caps involving linear Ce-O-Ce-O chains. Furthermore atomic hopping sequences triggered by high temperature during the molecular dynamics simulations have been compared to the irradiation-induced experimental hopping processes to explore similarities and differences.
Figure 5.6.4. Ce ion hopping on CeO2 (100) (Möbus, Saghi, Sayle, Bhatta, Stringfellow and Sayle, Advanced Functional Materials, 21(11) 1970 (2011)).
Electron beam nanofabrication of ferromagnetic particles and nanostructuresElectron beam (e-beam) fabrication of nanostructures by transmission electron microscopy (TEM) is presented as a top-down nanofabrication method for the sub-5 nm fabrication of structures that cannot usually be realised using resist based lithographic techniques or by the focused ion beam patterning methods.
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In a two-part study, at first the generation of nanostructures by materials removal using focused electron beams is described starting from either a homogeneous and free-standing nickel thin film, or starting from a nickel nanotip (Gnanavel, Yajid, Saghi, Peng, Inkson, Gibbs and Möbus, Applied Physics A: Materials Science and Processing, 102(1) 205-211 (2011)). Results achieved comprise arrays of nanoholes, nanobridges, and 3D sharpening of nickel tips down to sub-5nm radius. To exploit the full capability of modern TEM/STEM instruments, a variety of beam shapes (focused, astigmatic, field emission and thermionic guns) are applied for the first time, combining drilling with cutting and thinning actions, equivalent to an electron “scalpel”. In combination with tomographic large angle specimen tilt systems, it is shown how innovative sculpting in 3D can be achieved step-wise by ablation in different viewing directions. In the second part (Gnanavel, Kumar and Möbus, J Nanoscience and Nanotechnology, 11(2) 1019-1024 (2011)) pure Ni is replaced by NiF2 as a precursor material and the electron beam is used as a tool to preferentially ablated fluorine, leaving pure Ni behind. The nanoparticulate structures achieved are synthesised by nucleation and growth and therefore classify as “bottom-up” nanofabrication, complementing the earlier sculpting approach. In detail, the electron beam converts the original salt crystal into an intermediate nanoporous/nanocomposite (metal-salt) material, before further irradiation leads to rather sudden collapse of the pores and growth of dense spherical metal particles (beads) of 10-600 nm size, under the influence of minimising surface tension.
Figure 5.6.5. Ni-fluoride salt to Ni-metal bead conversion under electron irradiation [3].
A piezoelectric goniometer inside a TEM goniometer.To achieve ultimate flexibility and precision for nanomanipulation experiments inside a TEM, the conventional electro-mechanical specimen control needs to be replaced with piezoelectric actuation. Our challenge was to build the world’s first piezoelectric “goniometer” with both rotational and translational degrees of freedom, which fits inside the hollow inner cylinder of a conventional TEM single tilt specimen holder. Our reversibly insertible instrument therefore does not need any modifications to the TEM, and can be applied across many compatible TEMs without adaptation (Guan, Lockwood, Inkson and Möbus, Microscopy and Microanalysis, 17(5)827-833 (2011). Furthermore, the built-in TEM goniometer remains fully functional and can be used “in series” or simultaneously to the piezoelectric goniometer. The main applications of the device are
for tomography and in-situ TEM. For computed axial tomography (CAT) it is important that projection images of the 3D object are available for every viewing direction. One problem of traditional goniometers is a limitation in tilt range to far below 180°, which causes distortions in tomographic reconstructions. We present acquisition series of a W-tip test object exceeding the important 180° limit, and also present an innovative magnetic sensor feedback mechanism as measure of tilt angle.
Figure 5.6.6. [4]: W tip (surface rendering left, and central cross section right) reconstructed from piezo-goniometric full tilt series free of “missing wedge artefacts”.
Our goniometer allows for two specimens to be placed into different mounts, one piezo-moveable and one fixed position, with both together movable by the TEM goniometer. This unique setup allowed us for the first time in the history of TEM to rotate one specimen against a second specimen (“Differential Tilt”) while at the same time translating one against the other. This is important for experiments with overlapping specimens, holographic and magnetic imaging modes, and especially for crystallography-specific contacting experiments (mechanical or electrical).
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6 Publications, 2011
7 PhD Awards, 2011
8 Current Research Sponsors
9 Grants and Contracts Awarded 2011
10 Personal Highlights 2011
11 Retired Academic Staff Profiles
12 Appendix: Annual Report 2012 (separate report)
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1. T Abdulla, A Yerokhin and R Goodall “Effect of Plasma Electrolytic Oxidation coating on the specific strength of open-cell aluminium foams”, Mate Des 32(7) (2011) 3742-3749.
2. M M Z Ahmed, B P Wynne, W M Rainforth and P L Threadgill “Through-thickness crystallographic texture of stationary shoulder friction stir welded aluminium”, Scripta Mat, 1(64) (2011) 45-48.
3. M N Ali and I U Rehman “An Auxetic structure configured as oesophageal stent with potential to be used for palliative treatment of oesophageal cancer; development and in vitro mechanical analysis”, J Mater Sci-Mat in Medicine, 22(11) (2011) 2573-2581.
4. K Anantheshwara, A J Lockwood, R K Mishra, B J Inkson and M S Bobji “Dynamical Evolution of Wear Particles in Nanocontacts”, Tribology Letters (2011) 1-7.
5. G S E Antipas, C Lekakou and P Tsakiropoulos “Microstructural characterisation of Al - Hf and Al - Li - Hf spray deposits”, Mater Charact, 62(4) (2011) 402-408.
6. M Ascenzi and G C Reilly “Bone tissue: Hierarchical simulations for clinical applications”, J Biomech, 44(2) (2011) 211/212.
7. I Atkin, R H Elder, G H Priestman, D C Sinclair and R W K Allen “High temperature oxygen separation for the sulphur family of thermochemical cycles - Part I: Membrane selection and flux testing”, Intl J of Hydrogen Energy, 36(17) (2011) 10614-10625.
8. K M Au, Z Lu, S J Matcher and S P Armes “Polypyrrole Nanoparticles: A Potential Optical Coherence Tomography Contrast Agent For Cancer Imaging”, Adv Mats, 23(48) (2011) 5792–5795.
9. M Audronis, S J Hinder, P Mack, V Bellido-Gonzalez, D Bussey, A Matthews and M A Baker “A comparison of reactive plasma pre-treatments on PET substrates by Cu and Ti pulsed-DC and HIPIMS discharges”, Thin Solid Films, 520(5) (2011) 1564-1570.
10. S Banfield, J C Avelar-Batista Wilson, G Cassar, A Leyland, A Matthews and J Housden “An investigation into the effect of Triode Plasma Oxidation (TPO) on the tribological properties of Ti6Al4V”, Surf Coat Technol, 206(7) (2011) 1955-1962.
11. J H Bell and J W Haycock “Next Generation Nerve Guides: Materials, Fabrication, Growth Factors, and Cell Delivery”, Tissue Eng Part B: Reviews, 8th December 2011.
12. H Beltran, M Prades, N Maso, E Cordoncillo and A R West “Enhanced Conductivity and Nonlinear Voltage-Current Characteristics of Nonstoichiometric BaTiO3 Ceramics”, J Am Ceram Soc, 94(9) (2011) 2951-2962.
13. L Ben and D C Sinclair “Anomalous Curie temperature behavior of A-site Gd-doped BaTiO3 ceramics: The influence of strain”, Appl Phys Lett, 98(9) (2011) 092907.
14. I Betancourt, G Hrkac and T Schrefl “Magnetic domain structure and magnetization reversal in amorphous microwires with circular anisotropy: A micromagnetic approach”, J Appl Phys, 109(1) (2011).
15. I Betancourt, G Hrkac and T Schrefl “Micromagnetic study of magnetic domain structure and magnetization reversal in amorphous wires with circular anisotropy”, J Magn Magn Mats, 323(9) (2011) 1134-1139.
16. S Bhakta, K H Gillingham, M Mirsaneh, C A Miller, I M Reaney, I M Brook, R van Noort R and P V Hatton “In vitro biocompatibility of modified potassium fluorrichterite and potassium fluorrichterite-fluorapatite glass-ceramics”, J Mat Sci-Mats Med, 22(9) (2011) 2065-2070.
17. R Bhattacharya and B P Wynne “Hot working and crystallographic texture analysis of magnesium AZ alloys”, Mat Sci Technol, 27(2) (2011) 461-477.
18. J J Biendicho and A R West “Thermally-induced cation disorder in LiFePO4”, Solid State Ionics 203(1) (2011) 33-36.
19. P A Bingham, A J Connelly, N J Cassingham and N C Hyatt “Oxidation state and local environment of selenium in alkali borosilicate glasses for radioactive waste immobilisation”, J Non-Cryst Solids, 357(14) (2011) 2726-2734.
20. P A Bingham, A J Connelly, N C Hyatt and R J Hand “Corrosion of glass contact refractories for the vitrification of radioactive wastes: A review”, Intl Mater Rev, 56(4) (2011) 226-242.
21. A J Bullock, A Mangera, S MacNeil and C R Chapple “Development of aseptically produced scaffolds for substitution urethroplasty”, British Journal of Surgery, 98 (2011) 54.
22. K T Butler, P E Vullum, A M Muggerud, E Cabrera and J H Harding “Structural and electronic properties of silver/silicon interfaces and implications for solar cell performance”, Phys Rev B (Condensed Matter and Materials Physics) 83(23) (2011) 235307.
23. G Cassar, S Banfield, J C A B Wilson, J Housden, A Matthews and A Leyland “Tribological properties of duplex plasma oxidised, nitrided and PVD coated Ti-6Al-4V”, Surf Coat Technol, 206(10) (2011) 1277-1287.
24. G Cassar, J C A B Wilson, S Banfield, J Housden, M Fenech, A Matthews and A Leyland “Evaluating the effects of plasma diffusion processing and duplex diffusion/PVD-coating on the fatigue performance of Ti-6Al-4V alloy”, Intl J of Fatigue, 33(9) (2011) 1313-1323.
6 Publications 2011
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25. A A Chaudhry, H Yan, K Gong, F Inam, G Viola, M J Reece, J B M Goodall, I Ur Rehman, F K McNeil-Watson, J C W Corbett, J C Knowles and J A Darr “High-strength nanograined and translucent hydroxyapatite monoliths via continuous hydrothermal synthesis and optimized spark plasma sintering”, Acta Biomat, 7(2) (2011) 791-799.
26. M A Chavda, M I Ojovan and S Zhang “Immobilization of Nuclear Waste Graphite Using the SiC Synthesis Route”, Proc WM’11 Conference, 27th February – 3rd March 2011, Phoenix, Arizona, WM – 11484, 12 p (2011).
27. G Chen, J Di, M Li, I M Reaney, Y Lei, H Xu, C Zhou, M Jiang, X Liu “Synthesis, microstructure and microwave dielectric properties of Ca4-xMgxLa2Ti5O17 ceramics”, J Mat Sci: Mats Elects (2011).
28. H Chen, C L Freeman and J H Harding “Charge disproportionation and Jahn-Teller distortion in LiNiO2 and NaNiO2: A density functional theory study”, Phys Rev B (Condensed Matter Mat Phys), 84(8) (2011) 085108.
29. X Cheng, F Liu, X Zeng, G Ungar, J Kain, S Diele, M Prehm and C Tschierske “Influence of flexible spacers on liquid-crystalline self-assembly of T-shaped bolaamphiphiles”, J Am Chem Soc, 133(2) (2011) 7872-7881.
30. F Claeyssens, K E Ranaghan, N Lawan, S J Macrae, F R Manby, J N Harvey and A J Mulholland “Analysis of chorismate mutase catalysis by QM/MM modelling of enzyme-catalysed and uncatalysed reactions”, Organic and Biomol Chem, 9(5) (2011) 1578-1590.
31. H E Colley, V Hearnden, A V Jones, P H Weinreb, S M Violette, S Macneil, M H Thornhill and C Murdoch “Development of tissue-engineered models of oral dysplasia and early invasive oral squamous cell carcinoma”, British Journal of Cancer, 105(10) (2011) 1582-1592.
32. A J Connelly, R J Hand, P A Bingham and N C Hyatt “Mechanical properties of nuclear waste glasses”, J Nuclear Mats, 408(2) (2011) 188-193.
33. A J Connelly, N C Hyatt, K P Travis, R J Hand and E R Maddrell “Predicting the preference for charge compensation in silicate glasses”, Phys Chem Glasses B, 52(2) (2011) 64-67.
34. A J Connelly, N C Hyatt, K P Travis, R J Hand, E R Maddrell and R J Short “The structural role of Zr within alkali borosilicate glasses for nuclear waste immobilisation” J Non-Cryst Solids, 357(7) (2011) 1647-1656.
35. A J Connelly, K P Travis, R J Hand, N C Hyatt and E Maddrell “Composition-Structure Relationships in Simplified Nuclear Waste Glasses: 1. Mixed Alkali Borosilicate Glasses”, J Am Ceram Soc, 94(1) (2011) 151-159.
36. A J Connelly, K P Travis, R J Hand, N C Hyatt and E Maddrell “Composition-Structure Relationships in Simplified Nuclear Waste Glasses: 2. The Effect of ZrO2 Additions”, J Am Ceram Soc, 94(1) (2011) 137-144.
37. J Corrochano, J C Walker, M Lieblich, J Ibanez and W M Rainforth “Dry sliding wear behaviour of powder metallurgy Al-Mg-Si alloy-MoSi2 composites and the relationship with the microstructure”, Wear, 270(9-10) (2011) 658-665.
38. J Corteen, W M Rainforth and I Todd “A mathematical approach to transformation toughening in bulk metallic glasses”, Scripta Mat, 65(6) (2011) 524-527.
39. A Covill, N C Hyatt, J Hill and N C Collier “Development of magnesium phosphate cements for encapsulation of radioactive waste”, Adv Appl Ceram, 110(3) (2011) 151-156.
40. P S Davies, B P Wynne, W M Rainforth, M J Thomas and P L Threadgill “Development of Microstructure and Crystallographic Texture during Stationary Shoulder Friction Stir Welding of Ti-6Al-4V”, Metall Mater Trans A, 42A(8) (2011) 2278-2289.
41. C Davoisne, M C Stennett, N C Hyatt, N Peng, C Jeynes and Lee WE “Krypton irradiation damage in Nd-doped zirconolite and perovskite”, J Nuclear Mats, (2011) 67-73.
42. J A Dawson, C L Freeman, L Ben, J H Harding and D C Sinclair “An atomistic study into the defect chemistry of hexagonal barium titanate”, J Appl Phys, 109(8) (2011) 084102.
43. J Dean, M T Bryan, N A Morley, G Hrkac, A Javed, M R J Gibbs and D A Allwood “Numerical study of the effective magnetocrystalline anisotropy and magnetostriction in polycrystalline FeGa films”, J Appl Phys, 110(4) (2011) 043902.
44. J Dean, A Kohn, A Kovacs, A Zeltser, M J Carey, G Hrkac, D A Allwood and T Schrefl “The formation mechanism of 360 degrees domain walls in exchange-biased polycrystalline ferromagnetic films”, J Appl Phys, 110(7) (2011) 073901.
45. R M Delaine-Smith and G C Reilly “The effects of mechanical loading on mesenchymal stem cell differentiation and matrix production”, Vitam Horm: Adv Res Appl, 87 (2011) 417-480.
46. F Diologent, R Goodall and A Mortensen “Activation volume in microcellular aluminium: Size effects in thermally activated plastic flow”, Acta Mat, 59(18) (2011) 6869-6879.
47. M Elawayeb, Y Peng and B J Inkson “Nanostructure and chemical characterisation of individual NiFe/Pt multilayer nanowires”, J Nanosci Nanotech, 11(9) (2011) 7777-7782.
48. T El-Sayed and R J Hand “Fractographic analysis of epoxy coated glass”, Ceram Intl (2011) available online.
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49. T El-Sayed and R J Hand “Modelling the strengthening of glass using epoxy based coatings”, J Europ Ceram Soc, 31(15) (2011) 2783-2791.
50. N J Emerson, M J Carré, G C Reilly and A C Offiah “Geometrically accurate 3D FE models from medical scans created to analyse the causes of sports injuries”, Procedia Eng, 13 (2011) 422-427.
51. PC Eves, M Baran, NA Bullet, L Way, D Haddow and S MacNeil “Establishing a transport protocol for the delivery of melanocytes and keratinocytes for the treatment of vitiligo”, Tissue Engineering (2011) Available online.
52. M C Ferrarelli, D Nuzhnyy, S Kamba, D C Sinclair and A R West “Microwave dielectric properties of Na1/2Bi1/2Cu2.82Mn0.18Ti4O12 ceramics”, IOP Conference Series: Mater Sci Eng, 18 (2011) 092004.
53. M C Ferrarelli, C C Tan and D C Sinclair “Ferroelectric, electrical, and structural properties of Dy and Sc co-doped BaTiO3”, J Mater Chem, 21(17) (2011) 6292-6299.
54. A Feteira, D Iddles, T Price, D Muir and I M Reaney “High-permittivity and low-loss microwave dielectric ceramics based on (x)RE(Zn1/2Ti1/2)O3-(1-x)
CaTiO3 (RE=La and Nd)”, J Am Ceram Soc, 94(3) (2011) 817-821.
55. P Fiorenza, V Raineri, M C Ferrarelli, D C Sinclair and R Lo Nigro “Nanoscale electrical probing of heterogeneous ceramics: The case of giant permittivity calcium copper titanate (CaCu3Ti4O 12)”, Nanoscale, 3(3) (2011) 1171-1175.
56. C Fiorica, R A Senior, G Pitarresi, F S Palumbo, G Giammona, P Deshpande and S MacNeil “Biocompatible hydrogels based on hyaluronic acid cross-linked with a polyaspartamide derivative as delivery systems for epithelial limbal cells”, Intl J Pharmaceutics, 414(1-2) (2011) 104-111.
57. C L Freeman, J A Dawson, H R Chen, J H Harding, L B Ben and D C Sinclair “A new potential model for barium titanate and its implications for rare-earth doping”, J Mater Chem, 21(13) (2011) 4861-4868.
58. C L Freeman, J H Harding, D Quigley and P M Rodger “Simulations of ovocleidin-17 binding to calcite surfaces and its implications for eggshell formation”, J Phys Chem Part C: Nanomaterials and Interfaces, 115(16) (2011) 8175-8183.
59. N F Garza-Montes-de-Oca, R Colás and W M Rainforth “On the damage of a work roll grade high speed steel by thermal cycling”, Engineering Failure Analysis, 18(6) (2011) 1576-1583.
60. N F Garza-Montes-de-Oca, R Colás and W M Rainforth “Failure Modes of the Oxide Scale Formed on a Work Roll Grade High Speed Steel”, Oxidation of Metals: an international journal of the science of gas-solid reactions, 76(3-4) (2011) 149-160.
61. N F Garza-Montes-de-Oca, R Colás and W M Rainforth “High temperature oxidation of a work roll grade high speed steel”, Oxidation of Metals: an international journal of the science of gas-solid reactions, 76(5-6) (2011) 451-468.
62. N F Garza-Montes-de-Oca, R Colás and W M Rainforth “On the damage of a work roll grade high speed steel by thermal cycling”, Engineering Failure Analysis, 18(6) (2011) 1576-1583.
63. A T Giddings, M C Stennett, D P Reid, E E McCabe, C Greaves and N C Hyatt “Synthesis, structure and characterisation of the n=4 Aurivillius phase Bi5Ti3CrO15”, J Solid State Chem, 184(2) (2011) 252-263.
64. M Gilbert, C Davoisne, M C Stennett, N C Hyatt, N Peng, C Jeynes and W E Lee “Krypton and helium irradiation damage in yttria-stabilised zirconia”, Materials Research Society Symp Proc, 1298 (2011) 197-202.
65. M Gilbert and J H Harding “Energetics of Ce and Pu incorporation into zirconolite waste-forms”, Phys Chem Chem Phys, 13(28) (2011) 13021-13025.
66. A A Gill and F Claeyssens “3D structuring of biocompatible and biodegradable polymers via stereolithography”, Methods in Molecular Biology, 695 (2011) 309-321.
67. T Gnanavel, S Kumar and G Möbus “In-situ fabrication of three dimensional nickel nanobeads by electron beam induced transformation”, J Nanosci Nanotech, 11(2) (2011) 1019-1024.
68. T Gnanavel and G Möbus “Tomographic nanofabrication with electron beams”, Proc Microsc Conf. (MC2011), DGE pub,W Jäger et al, eds, Kiel, Germany, IM3-P143 (2011).
69. T Gnanavel, M A M Yajid, Z Saghi, Y Peng, B J Inkson, M R J Gibbs and G Möbus “Electron beam nanofabrication of ferromagnetic nanostructures in TEM”, Appl Phys A: Mat Sci Proc, 102(1) (2011) 205-211.
70. J R A Godinho, S Piazolo, M C Stennett and N C Hyatt “Sintering of CaF2 pellets as nuclear fuel analog for surface stability experiments”, J Nucl Mats, 419(1-3) (2011) 46-51.
71. V Goian, S Kamba, S Greicius, D Nuzhnyy, S Karimi and I M Reaney “Terahertz and infrared studies of antiferroelectric phase transition in multiferroic Bi0.85Nd0.15FeO3”, J Appl Phys, 110(7) (2011) 074112.
72. S Goulart-Santos, R D Mancosu, C Godoy, A Matthews and A Leyland “Influence of surface hardening depth on the cavitation erosion resistance of a low alloy steel”, J ASTM Intl, 8(9) (2011) ISSN: 1546-962X pp12.
73. I Grammenos and P Tsakiropoulos “Study of the role of Hf, Mo and W additions in the microstructure of Nb-20Si silicide based alloys”, Intermetallics, 19(10) (2011) 1612-1621.
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74. N H Green, Q Huang, B M Corfe, J P Bury and S MacNeil “NF-κB is activated in oesophageal fibroblasts in response to a paracrine signal generated by acid-exposed primary oesophageal squamous cells”, Intl J Expl Pathology: mechanisms and models of disease, 92(5) (2011) 345-356.
75. W Guan, A Lockwood, B J Inkson and G Möbus “A piezoelectric goniometer inside a transmission electron microscope goniometer”, Microscopy and Microanalysis, 17(5) (2011) 827-833.
76. W Guan and G Möbus “Differential tilt between two specimen parts by an all piezo-electric miniaturised goniometer”, Proc Microsc Conf (MC2011), DGE publ, W Jäger et al, eds, Kiel, Germany, IM6-P180 (2011).
77. J N Hart, N L Allan and F Claeyssens “Ternary silicon germanium nitrides: A class of tunable band gap materials”, Phys Rev B (Condensed Matter and Materials Physics), 84 (2011) 245209.
78. J W Haycock “3D cell culture: a review of current approaches and techniques”, Methods in Molecular Biology, 695 (2011) 1-15.
79. T J Hayward, A D West, K J Weatherill, T Schrefl, I G Hughes and D A Allwood “Nanomagnetic engineering of the properties of domain wall atom traps”, J Appl Phys, 110 (2011) 123918.
80. V Hearnden, S MacNeil and G Battaglia “Tracking nanoparticles in three-dimensional tissue-engineered models using confocal laser scanning microscopy”, Methods in Molecular Biology, 695 (2011) 41-51.
81. G L Hill, E Bailey, M C Stennett, N C Hyatt, E M Maddrell, P F McMillan and J A Hriljac “High-pressure and-temperature ion exchange of aluminosilicate and gallosilicate natrolite”, J Am Chem Soc, 133(35) (2011) 13883-13885.
82. J Hlinka, J Pokorny, S Karimi and I M Reaney “Angular dispersion of oblique phonon modes in BiFeO3 from micro-Raman scattering”, Phys Rev B (Condensed Matter and Materials Physics), 83(2) (2011) 020101.
83. M Holcombe, S Adra, M Bicak, S Chin, S Coakley, AI Graham, J Green, C Greenough, D Jackson, M Kiran, S MacNeil, A Maleki-Dizaji, P McMinn, M Pogson, R Poole, E Qwarnstrom, F Ratnieks, MD Rolfe, R Smallwood, T Sun and D Worth “Modelling Complex Biological Systems Using an Agent-based Approach”, Integrative Biology (2011).
84. A Howe “Simple approaches for solidification and diffusive homogenisation”, Ironmaking and Steelmaking, 38(7) (2011) 534-539.
85. G Hrkac, J Dean and D A Allwood “Nanowire spintronics for storage class memories and logic”, Phil Trans of the Royal Society A. Mathematical, Physical and Engineering Sciences, 369(1948) (2011) 3214-3228.
86. H Hussein, M Ojovan and H Kinoshita “Immobilisation of BaSO4: Phases and microstructure of OPC-BaSO4 system cured at an elevated temperature”, Proc WM’11 Conference, 27th February - 3rd March 2011, Phoenix, Arizona, WM – 11012, 11 p (2011).
87. Hussein, H Kinoshita and M Ojovan “Immobilisation of BaSO4: The effect of fine BaSO4 powder on the microstructure and strength of OPC- BaSO4 cured at an elevated temperature”, Proc NUWCEM2011, 1st Int Symp on Cement-based Materials for Nuclear Wastes, (O212) 10 p, Avignon, France 11-14.10.2011.
88. Y Iqbal, A Manan and I M Reaney “Low loss Sr1-
xCaxLa4Ti5O17 microwave dielectric ceramics”, Mat Res Bulletin, 46(7) (2011) 1092-1096.
89. M H Ismail, R Goodall, H A Davies and I Todd “Porous NiTi alloy by metal injection moulding/sintering of elemental powders: Effect of sintering temperature”, Mat Lett, 70(3) (2011) 142-145.
90. J W Jacobs and S J Matcher “Digital phase stabilization for improving sensitivity and degree of polarization accuracy in polarization sensitive optical coherence tomography” Proc SPIE 7889, 788938 (2011) doi:10.1117/12.874509.
91. T Jarvis, W Voice and R Goodall “The bonding of nickel foam to Ti-6Al-4V using Ti-Cu-Ni braze alloy”, Mat Sci Eng A: Structural Materials Properties Microstructure and Processing, 528(6) (2011) 2592-2601.
92. A Javed, N A Morley and M R J Gibbs “Effect of growth parameters on the structure and magnetic properties of thin polycrystalline Fe films fabricated on Si < 1 0 0 > substrates”, Appl Surf Sci, 257(13) (2011) 5586-5590.
93. A Javed, N A Morley, T Szumiata and M R J Gibbs “A comparative study of the microstructural and magnetic properties of < 1 1 0 > textured thin polycrystalline Fe100-xGax (10 <= x <= 35) films”, Appl Surf Sci, 257(14) (2011) 5977-5983.
94. M Jepson, X Liu, D Bell, D Ferranti, B J Inkson and C Rodenburg “Resolution limits of secondary electron dopant contrast in helium ion and scanning electron microscopy”, Microscopy and Microanalysis, 17(4) (2011) 637-642.
95. A C Johnson, S A Hayes and F R Jones “The role of matrix cracks and fibre/matrix debonding on the stress transfer between fibre and matrix in a single fibre fragmentation test”, Composites Part A: Applied Science and Manufacturing, 43(1) (2011) Available online.
96. R L Johnson-Wilke, D S Tinberg, C B Yeager, Y Han, I M Reaney, I Levin, D D Fong, T T Fister and S Trolier-Mckinstry “Tilt transitions in compressively strained AgTa0.5Nb0.5O3 thin films”, Phys Rev B (Condensed Matter and Materials Physics), 84(13) (2011) 134114.
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97. N G Jones and M Jackson “On mechanism of flow softening in Ti-5Al- 5Mo-5V-3Cr”, Mat Sci Technol, 27(6) (2011) 1025-1032.
98. R Kaewkhaw, A M Scutt and J W Haycock “Anatomical site influences the differentiation of adipose-derived stem cells for Schwann-cell phenotype and function”, Glia, 59(5) (2011)734-749.
99. K Kalantari, I Sterianou, S Karimi, M C Ferrarelli, S Miao, D C Sinclair and I M Reaney “Ti-doping to reduce conductivity in Bi0.85Nd 0.15FeO3 ceramics”, Advanced Functional Materials, 21(19) (2011) 3737-3743.
100. K Kanie, J Sekiguchi, X B Zeng, G Ungar and A Muramatsu “Phospholipids with a stimuli-responsive thermotropic liquid-crystalline moiety”, Chemical Communications, 47(24) (2011) 6885-6887.
101. P Kapranos “The Challenge of introducing ‘Environmental Issues’ into the teaching of Engineering Materials – A story of Reflective Teaching and Inquiry Based Learning”, 3rd Int. Materials Education Symposium, 7th-8th April 2011, Cambridge, UK.
102. D K Kasaragod, Z Lu and S J Matcher “A comparative study of the optical back-scattering properties of collagen fibers in bovine tendon and cartilage”, J Biomed Opt, 16 (2011) 080501.
103. D K Kasaragod, Z H Lu, J Jacobs and S J Matcher “Theoretical framework for the analysis of optical anisotropy in birefringent biological tissues with polarization-sensitive optical coherence tomography” Proc SPIE 8091 (2011) DOI: 10.1117/12.889208.
104. A S Khan, K R Hassan, S F Bukhari, F S L Wong and I U Rehman “Structural and in vitro adhesion analysis of a novel covalently coupled bioactive composite”, Journal of Biomedical Materials Research. Part B: Applied Biomaterials, 100B(1) (2011) 239-248.
105. C C Khaw, K B Tan, C K Lee and A R West “Phase equilibria and electrical properties of pyrochlore and zirconolite phases in the Bi2O3-ZnO-Ta2O5 system”, J Euro Ceram Soc, 32(3) (2011) 671-680.
106. A Kohn, J Dean, A Kovacs, A Zeltser, M J Carey, D Geiger, G Hrkac, T Schrefl and D A Allwood “Exchange-bias in amorphous ferromagnetic and polycrystalline antiferromagnetic bilayers: Structural study and micromagnetic modelling”, J Appl Phys, 109(8) (2011) 083924.
107. E Krajewska, C Lewis, C Staton, A Macgowan and S Macneil “New insights into induction of early-stage neovascularization in an improved tissue-engineered model of psoriasis”, J Tissue Engineering and Regenerative Medicine, 5(5) (2011) 363-374.
108. S Krohns, P Lunkenheimer, S Meissner, A Reller, B Gleich, A Rathgeber, T Gaugler, H U Buhl, D C Sinclair and A Loidl “The route to resource-efficient novel materials”, Nature Materials, 10(12) (2011) 899-901.
109. N Krstajic, D T D Childs, S J Matcher, D Livshits, A Shkolnik, I Krestnikov and R A Hogg “Swept-Source Laser Based on Quantum-Dot Semiconductor Optical Amplifier-Applications in Optical Coherence Tomography”, IEEE Photonics Technology Letters 23(11) (2011) 739-741.
110. N Krstajic, D Childs, N Peyvast, D Kasaragod, S J Matcher, I Krestnikov and R Hogg “Evaluation of a swept-laser optical coherence tomography light source based on a novel quantum-dot based semiconductor optical amplifier” Proc SPIE 8091 (2011) DOI: 10.1117/12.889247.
111. N Krstajic, D Childs, R Smallwood, R E Hogg and S J Matcher “Common path Michelson interferometer based on multiple reflections within the sample arm: sensor applications and imaging artefacts”, Meas. Sci Tech, 22(2) (2011) 027002.
112. N Krstaji, R Hogg and S J Matcher “Common path Fourier domain optical coherence tomography based on multiple reflections within the sample arm”, Opt Commun, 284(12) (2011) 3168-3172.
113. N Krstaji, R E Richard Hogg and S J Matcher “Common path FDOCT based on multiple reflections within the sample arm”, Proc. SPIE 7889, 78892K (2011) doi:10.1117/12.874669.
114. Y Lei, I M Reaney, Y C Liu, Y S Yin and G H Chen “Microwave dielectric properties and microstructures of RETiNbO6 (RE=La, Sm and Y)”, Adv Mater Res, 197-198 (2011) 285-289.
115. I Levin, M C Tucker, H Wu, V Provenzano, C L Dennis, S Karimi, T Comyn, T Stevenson, R I Smith and I M Reaney “Displacive phase transitions and magnetic structures in Nd-substituted BiFeO3”, Chem Mat, 23(8) (2011) 2166-2175.
116. D Li, X Tian, G Hu, Q Zhang, P Wang, P Sun, G Zhou, X Meng, J Yang, J Wu, B Jin, S Zhang, X Tao and Y Tian “Synthesis, crystal structures, photophysical properties, and bioimaging of living cells of bis-β-diketonate phenothiazine ligands and its cyclic dinuclear complexes”, Inorganic Chemistry, 50(17) (2011) 7997-8006.
117. M Li, D C Sinclair and A R West “Extrinsic origins of the apparent relaxorlike behavior in CaCu3Ti4O12 ceramics at high temperatures: A cautionary tale”, J Appl Phys, 109(8) (2011) 084106.
118. Y Li, G Zhang, X Zeng, J Cheng, M Gheorghe and S Elias “A modified estimation of distribution algorithm for numeric optimization”, Bio-Inspired Computing: Theories and Applications (BIC-TA), Sixth Intl Conf, Penang, (2011) 114-119.
119. Z Li and P Tsakiropoulos “Study of the effect of Ti and Ge in the microstructure of Nb-24Ti-18Si-5Ge in situ composite”, Intermetallics, 19(9) (2011) 1291-1297.
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120. Z Li and P Tsakiropoulos “The effect of Ge and Ti additions on the microstructures and properties of Nb-18Si based alloys”, Mat Res Soc Symp Proc, 1295 (2011) 379-384.
121. F Liu, M Prehm, X Zeng, G Ungar and C Tschierske “Two- and three-dimensional liquid-crystal phases from axial bundles of rodlike polyphiles: segmented cylinders, crossed columns, and ribbons between sheets”, Angewandte Chemie (International Edition), 50(45) (2011) 10599-10602.
122. X Liu, Z Wang and Zhang “Molten salt synthesis and characterization of titanium carbide-coated graphite flakes for refractory castable applications”, Intl J Appl Ceram Technol: ceramic product development and commercialization, 8(4) (2011) 911-919.
123. A J Lockwood, K Anantheshwara, M S Bobji and B J Inkson “Friction-formed liquid droplets”, Nanotechnology, 22(10) (2011) 105703.
124. A J Lockwood, A Padmanabhan, R J T Bunyan and B J Inkson “Nanoscale deformation of MEMS materials”, Mat Res Soc, 1297 (2011) pp6.
125. A J Lockwood, J Wedekind, R S Gay, J J Wang, M S Bobji, B Amavasai, M Howarth, G Moebus and B J Inkson “NanoLAB Triboprobe: Characterizing Dynamic Wear, Friction and Fatigue at the Nanoscale”, Mat Res Soc, 1297 (2011) 95-100.
126. Z H Lu, D K Kasaragod and S J Matcher “Optic axis determination by fibre-based polarization-sensitive swept-source optical coherence tomography”, Phys Med Biol, 56(4) (2011) 1105-1122.
127. Z H Lu, D K Kasaragod and S J Matcher “Performance comparison between 8- and 14-bit-depth imaging in polarization-sensitive swept-source optical coherence tomography”, Biomed Opt Express, 2(4) (2011) 794-804.
128. Z Lu, D K Kasaragod and S J Matcher “A method to calibrate phase fluctuation in polarization sensitive swept-source optical coherence tomography”, J Biomed Opt, 16 (2011) 070502.
129. Z Lu, D K Kasaragod and S J Matcher “Polarization-sensitive optical coherence tomography measurements using continuous polarization modulation with arbitrary phase modulation amplitude”, J Biomed Opt, 16 (2011) 070502.
130. Z Lu, D K Kasaragod and S J Matcher “A method to calibrate phase fluctuation in polarization-sensitive swept-source optical coherence tomography”, Proc SPIE 8091 (2011) DOI: 10.1117/12.889613.
131. Z H Lu, D K Kasaragod and S J Matcher “Performance comparison between 8 and 14 bit-depth imaging in polarization-sensitive swept-source optical coherence tomography”, Proc. SPIE 7889, 78892F (2011) doi:10.1117/12.874605.
132. Z H Lu, D H K Kasaragod and S J Matcher “Optic axis determination by fiber-based polarization-sensitive swept-source optical coherence tomography” Proc SPIE 7889, 78890W (2011) doi:10.1117/12.875081.
133. A Ma, B Zhao, A J Bentley, A Brahma, S MacNeil, F L Martin, S Rimmer and N J Fullwood “Corneal epithelialisation on surface-modified hydrogel implants - Artificial cornea”, J Mat Sci -Materials in Medicine, 22(3) (2011) 663-670.
134. L Ma and W M Rainforth “A Study of Biolox® delta Subject to Water Lubricated Reciprocating Wear”, Tribology International, 43(10) (2011) 1872-1881.
135. S MacNeil, S Bains, C Johnson, J M Idée, C Factor, G Jestin, N Fretellier and S K Morcos “Gadolinium contrast agent associated stimulation of human fibroblast collagen production”, Investigative Radiology, 46(11) (2011) 711-717.
136. S MacNeil, J Shepherd and L Smith “Production of tissue-engineered skin and oral mucosa for clinical and experimental use”, Methods in Molecular Biology, 695 (2011) 129-153.
137. A Mangera, A Bullock, S MacNeil and C R Chapple “comparative investigation of seven candidate scaffolds for the production of an autologous tissue engineered connective tissue for use in stress urinary incontinence and pelvic organ prolapsed”, Neurourology and Urodynamics, 30(6) (2011) 868-870.
138. A Mangera, A J Bullock, C R Chapple and S Macneil “Are biomechanical properties predictive of the success of prostheses used in stress urinary incontinence and pelvic organ prolapse? A systematic review”, Neurourology and Urodynamics, (2011) Available online.
139. A Mangera, A J Bullock, S MacNeil and C R Chapple “Creating a tissue engineered prosthesis for stress urinary incontinence and pelvic organ prolapse, which scaffold?”, British Journal of Surgery, 98(4/5) (2011) Conference Proceedings.
140. A Mangera, AJ Bullock, S MacNeil and C R Chapple “Engineering a novel tissue engineered autologus prosthesis for use in stress urinary incontinence (SUI) and pelvic organ prolapse (POP) repair”, British Journal of Surgery, 98(6) (2011) E6.
141. A Mangera, AJ Bullock, S MacNeil and C R Chapple “Increasing collagen production and contraction with ascorbate in a tissue engineered autologus prosthesis for use in the treatment of stress urinary incontinence (SUI) and pelvic organ prolapse (POP)”, British Journal of Surgery, 98(6) (2011) E7.
142. A Mangera, AJ Bullock, S MacNeil and C R Chapple “The effect of scaffold restraint on the properties of tissue engineered prostheses being developed for use in stress urinary incontinence (SUI) and pelvic organ prolapse (POP)”, European Urology, 10(2) (2011) 291.
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143. N Masó, D I Woodward, P A Thomas, A Varez and A R West “Structural characterisation of ferroelectric Ag2Nb4O11 and dielectric Ag2Ta4O11”, J Mater Chem, 21(8) (2011) 2715-2722.
144. N Masó, D I Woodward, A Varez and A R West “Polymorphism, structural characterisation and electrical properties of Na2Nb4O11”, J Mater Chem, 21(32) (2011)12096-12102.
145. N Masó, X Yue, T Goto and A R West “Frequency-dependent electrical properties of ferroelectric BaTi2O5 single crystal”, J Appl Phys, 109(2) (2011) pp8.
146. S J Matcher “Practical aspects of OCT imaging in tissue engineering”, Methods Mol Biol, 695 (2011) 261-280.
147. S J Matcher “Oximetry”, in Handbook of Biophotonics, Ed Jürgen Popp, Valery V Tuchin, Arthur Chiou, Stefan H Heinemann, Wiley-VCH (2011).
148. A Matthews “The UK surface engineering market”, T Met Finish, 89(2) (2011) 69-70.
149. F Maxim, P M Vilarinho, P Ferreira, I M Reaney and I Levin “Kinetic study of the static hydrothermal synthesis of BaTiO3 using titanate nanotubes precursors”, Cryst Growth Des, 11(8) (2011) 3358-3365.
150. J McGann and M I Ojovan “The Synthesis of Graphite-Glass Composites Intended for the Immobilisation of Waste Irradiated Graphite”, J Nucl Mater, 413 (2011) 47-52.
151. V Melissinaki, A A Gill, I Ortega, M Vamvakaki, A Ranella, C Fotakis, M Farsari and F Claeyssens “Direct laser writing of polylactide 3D scaffolds for Neural Tissue Engineering Applications”, Biofabriction, 3 (2011) 045005.
152. R J Milne, A J Lockwood and B J Inkson “Size-dependent deformation mechanisms of Al nanopillars”, J Phys D: Applied Physics, 44(48) (2011) 485301.
153. L Miranda, K Boulahya, M Hernando, D C Sinclair, F Jimenez-Villacorta, A Varela, J M Gonzalez-Calbet and M Parras “Structure-Composition-Property Relationships of 6H-BaTi1-
yCoyO3-delta (0.1 <= y <= 0.4)”, Chem Mat, 23(4) (2011) 1050-1060.
154. M Mirsaneh, B E Hayden, S Miao, J Pokorny, S Perini, E Furman, M T Lanagan, R Ubic and I M Reaney “High throughput synthesis and characterization of the PbnNb 2O5+n (0.5 < n < 4.1) system on a single chip”, Acta Mat, 59(5) (2011) 2201-2209.
155. M Mirsaneh, I M Reaney, Y Han, I Sterianou and O P Leisten “Low sintering temperature high permittivity glass ceramic composites for dielectric loaded microwave antennas”, Adv Appl Ceram, 110(7) (2011) 387-393.
156. G Möbus, Z Saghi, U M Bhatta, and I M Ross “Aberration corrected TEM of irradiation induced atomic hopping processes on various ceria surfaces observed in-situ”, Proc Microsc Conf (MC2011), DGE publ, W Jäger et al, eds, Kiel, Germany, IM2-P119 (2011).
157. G Möbus, Z Saghi, D C Sayle, U M Bhatta, A Stringfellow and T X T Sayle “Dynamics of Polar Surfaces on Ceria Nanoparticles Observed In Situ with Single-Atom Resolution”, Adv Funct Mats, 21(11) (2011) 1971-1976.
158. N A Morley, D Dhandapani, A Rao, H Al Qahtani, M R J Gibbs, M Grell, D Eastwood and B K Tanner “Polymeric spin-valves at room temperature”, Synthetic Metals, 161(7-8) (2011) 558-562.
159. C Morrison, L Saharan, G Hrkac, T Schrefl, Y Ikeda, K Takano, J J Miles and T Thomson “Inter/intra granular exchange and thermal activation in nanoscale granular magnetic materials”, Appl Phys Lett, 99(13) (2011) 132507 pp3.
160. C Murray-Dunning, S L McArthur, T Sun, R McKean, A J Ryan and J W Haycock “Three-dimensional alignment of schwann cells using hydrolysable microfiber scaffolds: strategies for peripheral nerve repair”, Methods in Molecular Biology, 695 (2011) 155-166.
161. R Nazir, N Iqbal, A S Khan, A Akram, A Asif, A A Chaudhry, I U Rehman and R Hussain “Rapid synthesis of thermally stable hydroxyapaptite”, Ceram Intl, 38(1) (2011) 457-462.
162. M I Ojovan, G A Varlackova, Z I Golubeva and O N Burlaka “Long-term field and laboratory leaching tests of cemented radioactive wastes”, J Hazard Mater, 187 (2011) 296-302.
163. M I Ojovan and W E Lee “Glassy wasteforms for nuclear waste immobilisation”, Metal Mater Trans A, 42(4) (2011) 837-851.
164. M I Ojovan and W E Lee “Glassy and glass composite nuclear wasteforms”, Ceram Trans, 227 (2011) 203-216.
165. M I Ojovan “Rydberg Matter Clusters: Theory of Interaction and Sorption Properties”, J Clust Sci, (2011) 1-12.
166. M I Ojovan (Editor) “Handbook of advanced radioactive waste conditioning technologies”, ISBN 1 84569 626 3. Woodhead Publishing Series in Energy No 12, Oxford, 512 (2011).
167. M I Ojovan “Radioactive waste characterisation and selection of conditioning technologies”, in: Handbook of advanced radioactive waste conditioning technologies. Edited by M I Ojovan. p. 1-16, Woodhead, Oxford (2011).
168. M I Ojovan P P Poluektov and V A Kascheev “Super-deep HLW self-disposal option”, Proc. WM’11 Conference, 27th February – 3rd March 2011, Phoenix, Arizona, WM – 11065, 10 p (2011).
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169. M I Ojovan, G A Varlakova, Z I Golubeva and O N Burlaka “Leaching of radionuclides from cementitious wasteforms in laboratory and field conditions”, Proc NUWCEM2011, 1st Int Symp on Cement-based Materials for Nuclear Wastes. (P38) 6 p, Avignon, France 11-14.10.2011.
170. M Z Omar, H V Atkinson and P Kapranos “Thixotropy in semi solid steel slurries under rapid compression”, Metal Mat Trans A, 42A (2011) 2011—2807.
171. D S G Ong, J S Ng, Y L Goh, C H Tan, S Zhang and J P R David “InAlAs avalanche photodiode with type-II superlattice absorber for detection beyond 2 μm”, IEEE Transactions on Electron Devices, 58(2) (2011) 486-489.
172. R A M Osman and A R West “Electrical characterization and equivalent circuit analysis of (Bi1.5 Zn0.5)(Nb0.5Ti1.5)O-7 Pyrochlore, a relaxor ceramic”, J Appl Phys, 109(7) (2011) 074106.
173. E J Palmeire, P Cizek, F Bai, R M Poths, J Turner, B P Wynne and W M Rainforth “The Use of Fe-30% Ni and Fe-30% Ni-Nb Alloys as Model Systems for Studying the Microstructural Evolution during the Hot Deformation of Austenite”, Mater Manuf Process, 26(1) (2011) 127-131.
174. E Pamula, J Kokoszka, K Cholewa-Kowalska, M Laczka, L Kantor, L Niedzwiedzki, G C Reilly, J Filipowska, W Madej, M Kolodziejczyk, G Tylko and A M Osyczka “Degradation, Bioactivity, and Osteogenic Potential of Composites Made of PLGA and Two Different Sol-Gel Bioactive Glasses”, Annals of Biomed Eng, 39(8) (2011) 2114-2129.
175. L B Parsons and R Goodall “Testing the fracture behaviour of chocolate”, Physics Education, 46(1) (2011) 50-56.
176. J M Patterson, A J Bullock, S MacNeil and C R Chapple “Methods to reduce the contraction of tissue-engineered buccal mucosa for use in substitution urethroplasty”, 60(4) (2011) 856-861.
177. A J Pearson, S A Boden, D M Bagnall, D G Lidzey and C Rodenburg “Imaging the bulk nanoscale morphology of organic solar cell blends using helium ion microscopy”, Nano Letters: a journal dedicated to nanoscience and nanotechnology, 11(10) (2011) 4275-4281.
178. C Pegoraro, S MacNeil and G Battaglia “Polymersome macromolecule delivery across intact human skin”, Tech Proc of NSTI Nanotechnology Conference and Expo, NSTI-Nanotech 2011 3: 428-431.
179. X Peng, A Matthews and S Xue, “Plasma-based processes and thin film equipment for nano-scale device fabrication”, J Mater Sci, 46(1) (2011) 1-37.
180. Y Peng, T Cullis, I Luxmoore and B Inkson “Electrical properties of individual CoPt/Pt multilayer nanowires characterized by in situ SEM nanomanipulators”, Nanotech, 22(24) (2011) 245709.
181. V Percec, S D Hudson, M Peterca, P Leowanawat, E Aqad, R Graf, H W Spiess, X Zeng, G Ungar and P A Heiney “Self-repairing complex helical columns generated via kinetically controlled self-assembly of dendronized perylene bisimides”, J Am Chem Soc, 133(45) (2011) 18479-18494.
182. V Percec, M Peterca, T Tadjiev, X Zeng, G Ungar, P Leowanawat, E Aqad, M R Imam, B M Rosen, U Akbey, R Graf, S Sekharan, D Sebastiani, H W Spiess, P A Heiney and S D Hudson “Self-assembly of dendronized perylene bisimides into complex helical columns”, J Am Chem Soc, 133(31) (2011) 12197-12219.
183. J D Plummer, R Goodall, I A Figueroa, I Todd “A study of mechanical homogeneity in as-cast bulk metallic glass by nanoindentation”, J Non-Cryst Solids, 357(3) (2011) 814-819.
184. J D Plummer and I Todd “Implications of elastic constants, fragility, and bonding on permanent deformation in metallic glass”, Appl Phys Lett, 98(2) (2011) 021907 pp3.
185. J Pokorny, U M Pasha, L Ben, O P Thakur, D C Sinclair and I M Reaney “Use of Raman spectroscopy to determine the site occupancy of dopants in BaTiO3”, J Appl Phys, 109(11) (2011) 114110.
186. J Poole, S MacNeil and S Rimmer “Semicontinuous emulsion polymerization of butyl methacrylate and 1, 3-butadiene in the presence of cyclodextrins and cytocompatibility of dicarboxylic acid telechelic oligo(butyl methacrylate)s derived from ozonolysis of the latexes”, Macromol Chem Phys, 212(18) (2011) 2043-2051.
187. M Prehm, F Liu, X Zeng, G Ungar and C Tschierske “Axial-bundle phases - New modes of 2D, 3D, and helical columnar self-assembly in liquid crystalline phases of bolaamphiphiles with swallow tail lateral chains”, J Am Chem Soc, 133(13) (2011) 4906-4916.
188. D Quigley, C L Freeman, J H Harding and P M Rodger “Sampling the structure of calcium carbonate nanoparticles with metadynamics”, J Chem Phys, 134(4) (2011) 044703.
189. I M Reaney, D I Woodward and C A Randall “Displacive phase transitions and intermediate structures in perovskites”, J Am Ceram Soc, 94(7) (2011) 2242-2247.
190. N Reeves-Mclaren, M C Ferrarelli, Y Tung, D C Sinclair and A R West “Synthesis, structure and electrical properties of Cu3.21Ti1.16Nb2.63O12 and the CuOx-TiO2-Nb2O5 pseudoternary phase diagram”, J Solid State Chem, 184(7) (2011) 1813-1819.
191. N Reeves-McLaren, R I Smith and A R West “Lithium-Ion Conduction Pathways in Complex Lithium Spine Is Li2MGe3O8 (M = Ni or Zn)”, Chem Mat, 23(15) (2011) 3556-3563.
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192. R Ristić, E Babić, D Paji, K Zadro, I A Figueroa, H A Davies, I Todd, A Kurumovi and M Stubiar “Mechanical and magnetic properties of Cu55Hf45-
xTix metallic glasses”, Solid State Comm, 151(14-15) (2011) 1014-1017.
193. R Ristić, E Babić, M Stubičar, A Kuršumović, J R Cooper, I A Figueroa, H A Davies, I Todd, L K Varga and I Bakonyi “Simple correlation between mechanical and thermal properties in TE-TL (TE = Ti,Zr,Hf;TL = Ni,Cu) amorphous alloys”, J Non-Cryst Solids, 357(15) (2011) 2949-2953.
194. C Rodenburg, X Liu, M A E Jepson, S A Boden and G Brambilla “Surface morphology of silica nanowires at the nanometer scale” J Non-Cryst Solids”, 357(15) (2011) 3042-3045.
195. P B Rose, D I Woodward, M I Ojovan, N C Hyatt and W E Lee “Crystallisation of a simulated borosilicate high-level waste glass produced on a full-scale vitrification line”, J Non-Cryst Solids, 357(15) (2011) 2989-3001.
196. R M Rumney, A Sunters, G C Reilly and A Gartland “Application of multiple forms of mechanical loading to human osteoblasts reveals increased ATP release in response to fluid flow in 3D cultures and differential regulation of immediate early genes”, J Biomech, 45(3) (2011) 540-554.
197. Y Safaei-Naeini, F Golestani-Fard, F Khorasanizadeh, M Aminzare and S Zhang “Low temperature molten salt synthesis of nano crystalline MgAl2O4 powder”, Iranian J Mat Eng, 8(3) (2011) 23-28.
198. L Saharan, C Morrison, J J Miles, T Thomson, T Schrefl and G Hrkac “Angle dependence of the switching field of recording media at finite temperatures”, J Appl Phys, 110 (2011) 103906.
199. P Sarker, J Shepherd, K Swindells, I Douglas, S MacNeil, L Swanson and S Rimmer “Highly branched polymers with polymyxin end groups responsive to Pseudomonas aeruginosa”, Biomacromolecules, 12(1) (2011) 1-5.
200. T X Sayle, B J Inkson, A Karakoti, A Kumar, M Molinari, G Möbus, S C Parker, S Seal and D C Sayle “Mechanical properties of ceria nanorods and nanochains; the effect of dislocations, grain-boundaries and oriented attachment”, Nanoscale 3(4) (2011) 1823-1837.
201. L Scelsi, A Hodzic, C Soutis, S A Hayes, S Rajendran, M A AlMa’adeed and R Kahraman “A review on composite materials based on recycled thermoplastics and glass fibres”, Plastics Rubber and Composites, 40(1) (2011) 1-10.
202. L Schulz, L Nuccio, M Willis, P Desai, P Shakya, T Kreouzis, V K Malik, C Bernhard, F L Pratt, N A Morley, A Suter, G J Nieuwenhuys, T Prokscha, E Morenzoni, W P Gillin and A J Drew “Engineering spin propagation across a hybrid organic/inorganic interface using a polar layer”, Nature Materials, 10(1) (2011) 39-44.
203. M Selim, A J Bullock, K A Blackwood, C R Chapple and S MacNeil “Developing biodegradable scaffolds for tissue engineering of the urethra”, British Journal of Urology (BJU) Intl, 107(2) (2011) 296-302.
204. Z Shamsudin, A Hodzic, C Soutis, R J Hand, S A Hayes and I P Bond “Characterisation of thermo-mechanical properties of MgO-Al2O3-SiO2 glass ceramic with different heat treatment temperatures”, J Mat Sci, 46(17) (2011) 5822-5829.
205. J Shepherd, P Sarker, S Rimmer, L Swanson, S MacNeil and I Douglas “Hyperbranched poly(NIPAM) polymers modified with antibiotics for the reduction of bacterial burden in infected human tissue engineered skin”, Biomat, 32(1) (2011) 258-267.
206. A T Sidambe, I A Figueroa, H Hamilton and I Todd “Improved Processing of Titanium Alloys by Metal Injection Moulding”, IOP Conf Ser: Mat Sci and Eng, 26 (2011) 012005.
207. A T Sidambe, I A Figueroa, H G C Hamilton and I Todd “Taguchi optimization of mim titanium sintering”, Intl J of Powder Metallurgy, 47 (2011) 21-28.
208. L Smith ands MacNeil “State of the art in non-invasive imaging of cutaneous melanoma”, Skin Res Tech, 17(3) (2011) 257-259.
209. L E Smith, V Hearnden, Z Lu, R Smallwood, K D Hunter, S J Matcher, M H Thornhill, C Murdoch and S MacNeil “Evaluating the use of optical coherence tomography for the detection of epithelial cancers invitro”, J Biomed Optics, 16(11) (2011) 116015.
210. J Squire, E R Maddrell, N C Hyatt and M C Stennett “Developing the plutonium disposition option: Ceramic processing concerns”, Ceram Trans, 227 (2011) 241-249.
211. M Steeper, M Jackson, P Madin and K Ridal “Advances in metal manufacturing technologies”, Ironmaking and Steelmaking, 38(4) (2011) 241-249.
212. M C Stennett, I J Pinnock and N C Hyatt “Rapid synthesis of Pb-5(VO4)(3)I, for the immobilisation of iodine radioisotopes, by microwave dielectric heating”, J Nuclear Materials, 414(3) (2011) 352-359.
213. L Sun, K Muszka, B P Wynne and E J Palmiere “The effect of strain path reversal on high-angle boundary formation by grain subdivision in a model austenitic steel”, Scripta Mat, 64(3) (2011) 280-283.
214. T Szumiata, K Brzózka, M Gawroćski, B Górka, A Javed, N A Morley and M R J Gibbs “Structural and magnetic ordering in Fe-Ga thin films examined by Mössbauer spectrometry”, Acta Physica Polonica. Series A: General Physics, Physics of Condensed Matter, Optics and Quantum Electrodynamics, 119(1) (2011) 21-23.
Materials@Sheffield 2012
63Materials Science & Engineering, The University of Sheffield
Publications6
215. S L Tan, S Zhang, W M Soong, Y L Goh, L J J Tan, J S Ng, J P R David, I P Marko, A R Adams, S J Sweeney and J Allam “GaInNAsSb/GaAs photodiodes for long-wavelength applications”, IEEE Elect Dev Lett, 32(7) (2011) 919-921.
216. D Tian, X Zeng and J Keane “Core-generating approximate minimum entropy discretization for rough set feature selection in pattern classification”, Intl J Approx Reason, 52(6) (2011) 863-880.
217. D S Tinberg, R L Johnson-Wilke, D D Fong, T T Fister, S K Streiffer, Y S Han, I M Reaney and S Trolier-McKinstry “Octahedral tilt transitions in relaxed epitaxial Pb(Zr1-xTix)O-3 films”, J Appl Phys, 109(9) (2011) 094104.
218. R Torchio, S Pascarelli, O Mathon, C Marini, S Anzellini, P Centomo, C Meneghini, S Mobilio, N A Morley and M R J Gibbs “Structure and magnetism in compressed iron-cobalt alloys”, High Pressure Research, 31(1) (2011) 148-152.
219. P Tsakiropoulos, K Zelenitsas and N Vellios “Study of the effect of Al, Cr and Sn additions on the microstructure and properties of Nb silicide based alloys”, MRS Proc, 1295 (2011) 367-372.
220. G Ungar, C Tschierske, V Abetz, R Holyst, M A Bates, F Liu, M Prehm, R Kieffer, X Zeng, M Walker, B Glettner and A Zywocinski “Self-assembly at different length scales: Polyphilic star-branched liquid crystals and miktoarm star copolymers”, Adv Funct Mats, 21(7) (2011) 1296-1323.
221. G A Varlakova, A T Dyakonova, A I Netrusov and M I Ojovan “Microbiological Activities on Cementitious Waste Forms in a Shallow-Ground Repository”, J Mater Sci Eng, B1 (2011) 591-596.
222. G A Varlakova, A T Dyakonova, A I Netrusov and M I Ojovan “Microbiological activities in a shallow-ground repository with cementitious wasteforms”, Proc NUWCEM2011, 1st Int Symp on Cement-based Materials for Nuclear Wastes, (P39) 10 p, Avignon, France 11-14.10.2011.
223. P Viswanathan, S Chirasatitsin, G Reilly, A Engler and G Battaglia “3D cell instructive scaffolds to direct stem cell fate”, Tech Proc 2011 NSTI Nanotech Conf and Expo, NSTI-Nanotech (2011) 3: 256-259.
224. N G Walker, AR Mistry, L E Smith, P C Eves, G Tsaknakis, S Forster, S M Watt and S Macneil “A Chemically Defined Carrier for the Delivery of Human Mesenchymal Stem/Stromal Cells to Skin Wounds”, Tissue Eng. Part C. Methods, 18(2) (2011) 143-155.
225. N Wang, B Robaye, A Agrawal, G Reilly, J M Boeynaems and A Gartland “Deletion of the P2Y13 receptor leads to reduced bone turnover and protection from ovariectomy-induced bone loss”, Bone, 48 (2011) S227.
226. A T White and C K Chong “Rotational invariance in the three-dimensional lattice Boltzmann method is dependent on the choice of lattice”, J Computational Physics, 230(16) (2011) 6367-6378.
227. H Wu and A R West “Thermally-Induced Homogeneous Racemization, Polymorphism, and Crystallization of Pyroglutamic Acid”, Cryst Growth Des, 11(8) (2011) 3366-3374.
228. B Xiao, E J Palmiere, A A Howe and H C Carey “Multi-Pass Simulation of Heavy Plate Rolling Including Intermediate Forced Cooling”, J Iron and Steel Res Intl, 18 (2011) 506-510.
229. W Xie, G Möbus and S Zhang “Molten salt synthesis of silicon carbide nanorods using carbon nanotubes as templates”, J Mat, 21(45) (2011) 18325-18330.
230. F Yan, S Miao, I Sterianou, I M Reaney, M O Lai, L Lu, W D Song “Multiferroic properties and temperature-dependent leakage mechanism of Sc-substituted bismuth ferrite-lead titanate thin films”, Scripta Mat, 64(5) (2011) 458-461.
231. T Yasuda, T Shimizu, R Liu, G Ungar and T Kato “Electro-Functional Octupolar pi-Conjugated Columnar Liquid Crystals”, J Am Chem Soc, 133(34) (2011) 13437-13444.
232. J Ye, S Zhang and W E Lee “Novel low temperature synthesis and characterisation of hollow silicon carbide spheres”, Micro Meso Mats, 152(1) (2011) 25-30.
233. B S Yilbas, S S Akhtar, A Matthews and C Karatas “Laser remelting of zirconia surface: Investigation into stress field and microstructures”, Mater Manu Proc, 26(10) (2011) 1277-1287.
234. B S Yilbas, S S Akhtar, A Matthews, C Karatas and A Leyland “Microstructure and Thermal Stress Distributions in Laser Carbonitriding Treatment of Ti-6Al-4V Alloy”, J Manu Sci and Eng, 133(2) (2011)021013.
235. X Zeng, R Kieffer, B Glettner, C Nürnberger, F Liu, K Pelz, M Prehm, U Baumeister, H Hahn, H Lang, G A Gehring, C H M Weber, J K Hobbs, C Tschierske and G Ungar “Complex multicolor tilings and critical phenomena in tetraphilic liquid crystals”, Science, 331(6022) (2011) 1302-1306.
236. Q L Zhang, N Maso, Y Liu, H Yang and A R West “Voltage-dependent low-field resistivity of CaTiO3:Zn ceramics”, J Mater Chem, 21(34) (2011) 12894-12900.
237. Z Zhou, W M Rainforth, M H Gass, A Bleloch, A P Ehiassarian and P E Hovsepian “C/CrC nanocomposite coating deposited by magnetron sputtering at high ion irradiation conditions”, J Appl Phys, 110(7) (2011) 073301.
238. Z Zhou, I M Ross, L Ma, W M Rainforth, A P Ehiasarian and P Hovsepian “Wear of hydrogen free C/Cr PVD coating against Al2O3 at room temperature”, Wear, 271(9) (2011) 2150-2156.
Materials@Sheffield 2012
64 Materials Science & Engineering, The University of Sheffield
PhD
Aw
ards
7
7 PhD Awards 2011
Master of Philosophy (M Phil) 2011Feng Xue “Single-and-two colour tilings by X-shaped Bolaamphiphiles”. Supervisors: Prof G Ungar and Dr X Zeng.
Eng DAdrian Covill “Novel encapsulants for intermediate level waste in the UK nuclear industry”. Supervisor Prof N C Hyatt.
Doctor of Philosophy (PhD) 2011Sinan Al-Bermani “An investigation into microstructure and microstructural content of ALM T1-6a1-4v by electron beam melting”. Supervisor: Prof I Todd.
Peter Bailey “Through life monitoring of composites using embedded evanescent wave spectroscopy”. Supervisors: Dr S A Hayes and Prof R J Hand.
Muhammad Bashir “Alternative magnetic recording technologies”. Supervisors: Dr D A Allwood and Prof T Schrefl.
Mohd Bin Md Jamil “Self healing epoxy composites; Mechanistic Studies”. Supervisor: Prof F R Jones.
Keith Blackwood “Electron scaffolds for soft tissue engineering”. Supervisor: Prof S MacNeil.
Glenn Cassar “Improvement in the tribological characteristics of titanium alloys using duplex and hybrid intensified plasma treatments”. Supervisors: Dr A Leyland and Prof A Matthews.
Jitrin Chaiprapa “New supramolecular liquid crystal structures in wedge-shaped molecules”. Supervisor: Prof G Ungar.
Yao-Chang Chen “Synthesis and characterisation of Li rare earth-based oxide materials”. Supervisor: Prof A R West.
Robert Deffley “Development of processing strategies for the additive layer manufacture of aerospace components in inconel 718”. Supervisor: Prof I Todd.
Miriam Flores-Merino “Nanofunctionalization of hydrogels for biomedical applications”. Supervisors: Dr G Reilly and Dr G Battaglia.
Andrew Giddings “A study of structure-property relations in layered perovsites of the Aurivillius Family”. Supervisor: Prof N C Hyatt.
James Jacobs “Polarization sensitive optical cpherence tomography; applications in tissue engineering”. Supervisor: Dr S J Matcher.
Rossukon Kaewkhaw “Primary Schwann cells and adipose-derived stem cells for peripheral nerve repair”. Supervisor: Prof J W Haycock.
Sarah Karimikhoygani “Structure-property relations in rare earth doped BiFeO3”. Supervisor: Prof I M Reaney.
Hidayat Ullah Khan “Phase Transitions in Li-doped Ag(NbxTa1-x)O3 Perovskite Ceramics”. Supervisor: Prof I M Reaney.
Xiaobin Mang “Self-assembled liquid crystal nanostructures”. Supervisors: Dr X Zeng and Prof G Ungar.
Marzia Massignani “Polymersomes for intracellular delivery: mechanism of action and applications”. Supervisors: Prof J W Haycock and Dr G Battaglia.
Celia Murray-Dunning “Electrospun aligned biodegradable microfibers and plasma polyermerisation techniques to improce peripheral nerve repair”. Supervisors: Prof J W Haycock and Prof S MacNeil.
Vishwanathan Nagarajan “A new approach for modelling strain induced precipitation of niobium carbonitrides in austenite during multipass hot rolling”. Supervisor: Dr E J Palmiere.
Rozana Osman “Synthesis and characterisation of novel electronic ceramics”. Supervisor: Prof A R West.
PenChom Photjanataree “The interaction of functional plasma polymers with epoxy resins”. Supervisor: Prof F R Jones.
Abdul Rauf “Optical health monitoring of composites using self-sensing e-glass fibre waveguides”. Supervisor: Prof R J Hand.
Maria Enriqueta Real San Miguel “Complement activation at biomaterial surfaces”. Supervisors: Prof J W Haycock and Dr S L McArthur.
Mohamed Salem “The effect of processing conditions and cooling rate on the microstructure and properties of API X-70 and API X-100 steels”. Supervisor: Dr E J Palmiere.
Pierre Samson “Nanoindentation of polystyrene and polymethyl methacrylate coatings on a glass substrate”. Supervisor: Dr S A Hayes.
James Schofield “Vitrification of a chloride containing actinide waste surrogate”. Supervisors: Prof R J Hand and Dr P A Bingham.
Tutu Sebastian “Bi(Me)03-PbTio3 ceramics for high temperature piezoelectric applications”. Supervisor: Prof I M Reaney.
Thomas Smart “Amphiphilic block copolymer membranes”. Supervisor: Dr G Battaglia.
Mohd Sobri Idris “Synthesis and characterisation of lithium nickel manganese cobalt oxide as cathode material”. Supervisor: Prof A R West.
Timur Tadjiev “Crystal structures of helical columnar-conjugated systems and biodegradable polyester”. Supervisor: Prof G Ungar.
Wie Xie “Molten salt synthesis and characterisation of novel carbide materials”. Supervisors: Dr S Zhang and Dr G Moebus.
Zhaoxia Zhou “Oxidation and wear of TiAIN/VN multilayer PVD Hard Coatings”. Supervisor: Prof W M Rainforth.
Materials@Sheffield 2012
65Materials Science & Engineering, The University of Sheffield
Sponsors8
8 Current Research Sponsors
The Department of Materials Science and Engineering is very grateful to the organisations listed below for their material support of our research. Our level of research activity would have been impossible without their generous contributions.
ACTINET
Advanced Composites Group Ltd
Advantica Tech Ltd
Aggregate Industries Ltd
Airbus UK Ltd
Alcan Chemicals Ltd
Alcan Engineered Products
Alcan International plc
Allvac Ltd
American Chemical Society
Andrew Carnegie Scholarship
Anglo-Platinum SA
Arburg
Arcam
Armourers and Brasiers’ Company
Asian Development Bank
AT Poeton Ltd
Atomising Systems Ltd, Sheffield
Avesta Polarit
AVX, Coleraine
BAe Systems Plc
Biocompatibles
Biotechnology and Biological Sciences Research Council
Boeing
BP Exploration
British Aerospace Defence Ltd
British Coal Utilisation Research Association
British Council
British Energy Generation Ltd
British Glass
Brook Hansen Ltd
Brookhaven National Laboratory
Building Research Establishment
CAPES Programme, Brazilian Government
Caterpiller Inc
CBMM
Ceramaspeed Ltd, Kidderminster
CENIM, Madrid
Chinese Government
Chung-Shan Institute of Science and Technology, Taiwan
Colipa
CONACYT, Mexico
Cookson Matthey Ceramics plc
Cytec Engineering Materials
Danieli Davy Distington Ltd
Dan Spray
Delphi Diesel Systems Ltd
DERA, Malvern
DeWalt/Black and Decker UK Limited
DGP Group
Doncasters plc
Dormer Tools Ltd
Dow Corning Ltd
Dowding and Mills Ltd
DSTL
DSM, Gelen, The Netherlands
DTI
Dynamic Ceramic
EADS (UK and Germany)
Egide UK
Ekspan Ltd, Sheffield
Engineering and Physical Sciences Research Council (EPSRC)
Environment Agency
EU-ALFA Programme
European Regional Development Fund Objective 1
EU-Framework VII Initiative
EU-INTAS Programme
EU-NVOTO Programme
European Synchrotron Radiation Facility
European Owens Corning
First Subsea Ltd
Firth Rixon plc, Rotherham
Flow Science Inc.
Furlong Charitable Research Foundation
GEC-Marconi Research Centre
General Electric (ex Rare Earth Products (GE) Ltd, Widnes)
George Greensmith and Co Ltd, Sheffield
Glass Technology Services (GTS)
Glass Training Ltd
Government of Iran
Government of Libya
Government of Malaysia
Government of Mexico
Government of Pakistan
Government of Spain
Government of Thailand
Government of Turkey
Materials@Sheffield 2012
66 Materials Science & Engineering, The University of Sheffield
Spon
sors
8
Health and Safety Laboratory
Hereans Electro-Nite UK Ltd
Hitatchi Global Storage Technologies
Holset Turbochargers
Hydro Aluminium
Innoval Technology Ltd
Institute of Materials, Minerals and Mining
Intercytex Limited
International Atomic Energy Agency
International Centre for Diffraction Data, USA
Ion Coat Ltd
Ironmongers Company
Johnson Matthey plc
K B Alloys Inc
Keronite Ltd
King Mongkuts University, Thailand
Kirkstall Ltd
Lawrence Livermore Laboratory
Leverhulme Trust
London and Scandinavian Metallurgical Co Ltd, Rotherham
Lynwood Products
Magnesium Electron Ltd
Magnox Electric plc
Maharashra Institute of Technology, India
Mandeville of London Ltd
Materialise BV
Merck Ltd
METRIC (N8 Molecular Engineering Research Centre)
Metalysis Limited
Minelco Minerals
Ministry of Defence
Mitsubishi Heavy Industries, Japan
Morgan Advanced Ceramics
Morgan Electroceramics Ltd
National Environmental Research Council
National Institute for Health Research (NIHR)
National Nuclear Laboratory
National Physical Laboratory
National Synchrotron Light Source
NGF Europe Ltd
Nippon Sheet Glass
Novelis
Nuclear Decommissioning Authority (NDA)
Nuclear Energy Corporation of South Africa
Nuclear Technology Education Consortium
Orla Protein Technologies
Osaka Institute of Technology, Japan
Outokumpu Stainless
Owens Corning Fibreglass RV, Belgium
Particle Physics and Astronomy Research Council (PPARC)
Pilkington plc
Plasso Technology Ltd
POSCO, Pohang Steel Company, Korea
Powerwave Ltd Ilika Technology
Precision Products Ltd
PSI, Hailsham, East Sussex
Q Coat Ltd
Qinetiq Plc, Farnborough
Qinetiq, Malvern
Qinetiq MAST Innovative
Reference Metals Company Inc., USA
regeNer8
Renold Chain Ltd
The Research Council UK (RCUK)
Research Institute for Solid State Physics, Budapest, Hungary
Rolls-Royce plc
Reiter Automotive Management AG
Royal Society of Chemistry
Rutherford Appleton Laboratory
Sabic, The Netherlands
SAIT, Samsung Advanced Institute of Technology
Sandvik Osprey
Sarantel Ltd
Sellafield Limited
Sheffield Forgemasters Group, Sheffield
SIDERAR, Argentina
Silberline, Leven, UK
Siemens Industrial Turbines Ltd
Siemens VAI plc
SIRIM, Malaysia
Sumitomo Metal Industries, Ibaraki, Japan
Symmetry Medical
Synchrotron Radiation Source
Tata Iron and Steel Company Ltd, India
Tata Steel plc
Tata Aluminium Rolled Products
Tata, Construction and Industrial
Tata Engineering Steels Ltd, Rotherham
Tata, Research, Development and Technology (Tata Teesside Technology Centre)
Tata Research Development and Technology, Ijmuiden (Netherlands)
Tata Rail
Materials@Sheffield 2012
67Materials Science & Engineering, The University of Sheffield
Sponsors8
Tata, Research, Development and Technology (Tata Swinden Technology Centre)
Tata Steel Strip Products
Technical Fibre Products, Kendal, UK
Technology Strategy Board (TSB)
Technology Strategy Consultants
Tecvac Ltd
Thai Government
Thermometrics
The Royal Society
The Wellcome Trust
Timet
Timken Inc
Tinsley Wire, Sheffield
Top Box
Toyobo Limited, Japan
TWI
UNAM, Mexico City
United States Air Force
United States Department of Energy
University of Malaysia
University of Sheffield, Proof of Concept Fund
USA Center for Nuclear Waste Regulatory Analyses
Vesuvius Premier
Wallwork Heat Treatment Ltd
WBB plc
White Rose Consortium
Worshipful Company of Ironmongers
WRAP (Waste and Resources Action Plan, UK Government)
Wuhan Iron and Steel Company (WISCO)
Yorkshire Forward
York Pharma
Materials@Sheffield 2012
68 Materials Science & Engineering, The University of Sheffield
Gra
nts
9
Awarding Body Grant Holder/s Project Title Apportioned Award Value
PROCTOR AND GAMBLE PHARMACEUTICALS
Prof S MacNeil Proctor and Gamble £251,471.50
THE ROYAL ACADEMY OF ENGINEERING Dr S J Matcher Industrial Secondment £21,000.00
EPSRC Dr S A HayesEm Prof F R JonesDr Z Liu
Develop the casting of polymer adhesive/ carrier films £53,625.00
TECHNOLOGY STRATEGY BOARD
Dr A LeylandProf A Matthews
Novel Efficiency-Enhancing Duplex Treatments for Turbines (NEET) £595,500.00
EPSRC Prof I M Reaney New Perovskite Materials with Large Field-Induced Electromechanical Strains £30,703.00
POSCO Prof M R GibbsDr E J Palmiere
Effect of segregation elements and hot deformation on abnormal grain growth in GO-Silicon Steel
£28,948.00
EPSRC Dr S J Matcher KTA 200nm SLD £11,204.25
EPSRC Prof I M Reaney High temperature multi-layer actuators for diesel fuel injection systems £46,985.00
SMARTKEM LTD Dr F Claeyssens METRC STP Stage 2 Award SmartKem Ltd £1,000.00
EUROPEAN COMMISSION
Prof N C HyattProf W M Rainforth
EMMI £258,461.00
TISSUE REGENIX Prof S MacNeil Comparison of sterilisation methodologies on tissue recellularisation £20,003.00
DEFENCE SCIENCE AND TECHNOLOGY LABORATORY
Dr R GoodallProf I Todd CDE Micro-Truss Blast Resistance £12,516.40
EPSRCDr P A BinghamProf R J HandProf N C Hyatt
MBM ash in fibre glass insulation KTA proof of concept £49,343.00
KNOWLEDGE TRANSFER PARTNERSHIP
Prof J W Haycock To develop, evaluate and test a new mar-ketable bioactive coating £127,218.00
EPSRC Prof S MacNeilLANDSCAPE AWARD - Engineering Tissue Engineering and Regenerative Medicine ~ E-TERM
£37,722.00
TECHNOLOGY STRATEGY BOARD Dr S A Hayes To develop and commercially produce
bio-derived compostable biopolymer £19,195.65
EPSRC Prof J W HaycockProf S MacNeil
A high contrast emission diagnostic tool for early non-invasive cancer detection £24,851.50
EPSRC Dr M Jackson The development of direct manufacturing process for low cost titanium coil springs £37,567.00
9 Grants Awarded 2011
Materials@Sheffield 2012
69Materials Science & Engineering, The University of Sheffield
Grants
9
Awarding Body Grant Holder/s Project Title Apportioned Award Value
EPSRC Prof S MacNeilDr S J Matcher
Evaluation of a novel biocompatible polypyrrole nanoparticle optical contrast agent for OCT imaging
£42,420.10
EUROPEAN COMMISSION Prof S MacNeil CA-RoboCom £37,134.00
UNILEVER Prof B J Inkson Unilever PhD - factors in abrasive tooth cleaning - Consumables £5,000.00
EPSRCProf I M ReaneyProf W M Rainforth
Domain wall - Defect interactions in fer-roelectric thin films £393,648.00
SAVANNAH RIVER NUCLEAR SOLUTIONS, LLC
Dr P A BinghamProf R J Hand SRNL Modelling Development Stage 1 £25,532.00
NUFFIELD FOUNDATION Prof J W HaycockDevelopment and testing of neurophillic scaffold materials for peripheral nerve repair
£1,440.00
EUROPEAN COMMISSION Prof N C Hyatt WASTEKIT £33,036.00
TECHNOLOGY STRATEGY BOARD
Dr A LeylandProf A Matthews
Biomedical implant with Exceptional Resistance to Tribo-bio-corrosion and Inherent antimicrobial properties (BERTI)
£76,511.00
EPSRC Dr T Hayward MAGNETISM YOU CAN RELY ON £698,103.00
EUROPEAN COMMISSION
Dr R GoodallProf P Tsakiropoulos
Accelerated Metallurgy £444,967.00
EUROPEAN OFFICE OF AEROSPACE Dr S A Hayes Self healing inkjet composites £6,263.60
TISSUE REGENIX Prof S MacNeilComparison of sterilisation meth-odologies on tissue recellularisation CONTINUATION
£4,929.00
ROYAL HALLAMSHIRE HOSPITAL TRUST Prof S MacNeil Developing tissue engineered materials
for pelvic floor repair £36,816.30
EPSRC Prof I M Reaney The atomic resolution chemical structure of defects in multiferroic oxides £4,972.00
DOBENECK-TECHNOLOGIE-STIFTUNG
Prof I ToddProf W M Rainforth
MERCURY - PROBEAM EQUIPMENT £172,537.00
EPSRC Prof I Todd Anchorless selective laser melting (ASLM) of high temperature metals £76,645.00
EPSRC (KTA Fund) Prof D C SinclairDr R Elder (CBE)
Kickstart Funding for co-electrolysis using Solid Oxide Fuel Cells £39,524
EPSRC (KTA Fund)Prof W M Rainforth Prof D C Sinclair
Equipment funding for Thermal Conductivity Rig and High Temperature X-ray Diffractometer
£58,000
Materials@Sheffield 2012
70 Materials Science & Engineering, The University of Sheffield
Hig
hlig
hts
2011
10
10 Department Highlights 2011
Emeritus Prof Michael Cable• Presented the paper, “The classic texts of glass tech-
nology”, at the Society of Glass Technology Annual Meeting, Oxford, September.
• Gave a lecture, “Pioneers in optical glass manu-facture”, at the Association for the History of Glass, London, November.
Prof Neil Chapman was awarded the James Watt Medal of the Institution of Civil Engineers in respect of his paper, “A geological disposal facility for the UK’s radioactive wastes”, which was published in Energy (Proceedings of the Institution of Civil Engineers), 162, 183-192 (2009).
Dr Fred Claeyssens • Attended the Materials Research Society Fall meeting
in November 2011 and presented 2 talks (of which one invited) on his recent work on polymer scaffold fabrication for tissue engineering. Also he will be presenting his work on the Gordon conference on Biointerface science.
• Recently published 2 papers in Biofabrication which both were reported in the popular press. His last study on polymer-based nerve guidance conduits was reported on the BBC website and ~100 international news sites throughout the world. Also the local press picked up the press release and Dr Claeyssens gave a live 5 minute interview during BBC Sheffield’s ‘Drive Time’ program.
Pete Crawforth• Presented a paper at the 12th Conference on Titanium
in Beijing, China, June.
Andrew Cunliffe• Gave a presentation on predicting the properties
of high entropy alloys from electronic structure” at the Bulk Metallic Glass Symposium during the TMS Annual Meeting in Sand Diego, USA.
• Presented a poster, “Glass formation in a high entropy alloy”, at the International Symposium on Metastable Amorphous and Nano-Structures Materials in Gijon, Spain.
Emeritus Prof Fergus Gibb • Participated in a Workshop on “Pilot Testing Deep
Borehole Disposal of Nuclear Waste”, 26th October, Albuquerque, New Mexico. In its interim report President Obama’s Blue Ribbon Commission “identi-fied deep boreholes as a potentially promising tech-nology for geologic disposal that could increase the flexibility of the overall waste management system and therefore merits further research, development and demonstration”. A recommendation to this effect was made in its final report published in January 2012. The Deep Borehole Disposal Consortium (based on Sandia NL, Sheffield and MIT) convened the work-shop, attended by US Government and nuclear indus-try representatives to discuss how deep borehole disposal should be progressed.
• Took part in a 3-day conference/workshop on Geological Disposal of Radioactive Waste: Underpinning Science and Technology held at Loughborough University, 18th-20th October, and gave a presentation, “Deep borehole disposal of higher burn-up nuclear wastes”, co-authored with K P Travis and K W Hesketh. The meeting was convened by the Royal Society of Chemistry, The Geological Society, the Royal Academy of Engineering, the Mineralogical Society and the Institution of Chemical Engineers among others and was sponsored by the Radioactive Waste Management Division of the Nuclear Decommissioning Authority. Its aim was to “showcase and publish research relevant to radioactive waste storage and disposal” by bringing together scientists, engineers and other specialists to discuss the chemical, geological, hydrological, bio-logical, materials, engineering and other issues associ-ated with the management and disposal of radioactive waste in the UK. The meeting was considered a great success by the sponsors.
Dr Russell Goodall• Was invited to give a lecture course on “Porous
Metals” at the Summer School in Materials Science, held at The National Autonomous University of Mexico (UNAM).
• Was invited to give a guest lecture “Doing More with Less; Efficiency in Engineering” to students at Sheffield International College, 19th October.
• Became Deputy Chair of the IoM3 Education Committee.
• Attended Euromat 2011 in Montpellier, France, and presented work on the PEO coating of foams (with Taha Abdualla and Aleksey Yerokhin) and on the use of metal foams in Stirling engines (with Erardo Elizondo and collaborators in Mechanical Engineering).
Miss Sarah Haine • Attended SMEA Conference on Materials Fit for
21st Century: processing for High Performance Applications, 21st and 22nd June, at The University of Sheffield.
• Presented on “Sustainable plate manufacturing at AISTech 2011, Indianapolis, USA, May.
• Presented on “Aspects of sustainable plate man-ufacturing” at METEC InSteelCon EECR 2011 – 1st International Conference on Energy Efficiency and CO2 Reduction in the Steel Industry, Düsseldorf, Germany, June.
Prof Russell Hand• Presented an invited paper, “Vitrification and durabil-
ity: strategies for vitrifying wastes containing chal-lenging anions” (co-authored with J M Schofield and P A Bingham) and another paper, “Relationships between the mechanical properties of silicate glass-es and chemical composition”, at the International Conference on the Chemistry of Glasses and Glass Forming Melts, Oxford, October.
Materials@Sheffield 2012
71Materials Science & Engineering, The University of Sheffield
Highlights 2011
10
• Had an invited visit to Gürallar Artcraft (a glassware manufacturer) in Kütahya, Turkey, 6th-9th January.
• Attended the Indo-UK Civil Nuclear Collaboration Review Meeting, Mamallapuram, India, 6th-9th March.
• Gave an invited lecture, “Towards stronger silicate glasses: a review of research into the mechanical properties of glasses”, at Şişecam 26 Cam Sempozyum (26th Şişecam Glass Symposium, Istanbul, Turkey, 27th May.
• Gave an invited lecture, “Mechanical properties of glasses, waste glass composition development and characterisation”, at the 10th Anniversary Glass Trend meeting in Zandvoort, The Netherlands, 7th-9th June.
• Acted as an external PhD examiner at the University of Aalborg, Denmark. The thesis submitted by Martin Jensen was entitled “Inhomogeneity in glass forming melts”. The defence took place on 30 September 2011.
• Attended the first Research Coordination meeting of the collaborative research project “Treatment of Irradiated Graphite to Meet Acceptance Criteria for Waste Disposal” held at the IAEA Vienna, 28th-30th November.
Prof John Harding• Presented a paper, “Controlling crystal growth with
organic molecules in aqueous systems”, at the RCS Materials Chemistry Meeting, Manchester, July.
• Presented a review on simulating the nucleation and growth of calcium carbonate at a WUN workshop “Mineralisation in corals”, York, July.
• Organised the annual Summer School in Molecular Simulation in Belfast and gave 4 lectures there as part of the course, July.
• Gave two invited presentations (one on Surface Science and Nanotechnology; the other on Simulation Methods) at an International Summer School “Nanotechnology and Virtual Reality”, St Poelten, Austria, July.
• Gave an Invited Talk “Simulation on the edge: the trials and tribulations of modelling interfaces” at the Annual General Meeting of CCP5, Bath, September.
• Organised a Symposium, “Nucleation and Growth of Biological and Biomimetic Materials”, at the MRS Fall Meeting, Boston, November, and pre-sented papers and posters.
Prof John Haycock• Gave an invited departmental seminar, “Bioengineering
peripheral nerve, biomaterials and stem cells”, at the Medical School University of Manchester, February.
• Gave an invited talk, “Adipose-derive stem cells for nerve repair”, to the Thai Stem Cell Meeting at the University of Sheffield, March.
• Gave an invited talk, “Bioengineering peripheral nerve”, to the Kroto Research Institute Annual Symposium, May.
• Gave an invited talk, “Rapid fabrication of bioac-tive surfaces”, to the Polymer Centre University of Sheffield, July.
• Gave an invited talk, “Fabrication of a medical device nerve guide”, to the Regener8 Annual Symposium, Manchester, September.
• Gave an invited talk, “Controlling biological function using polymer interfaces and surfaces”, to the SSBII, Port Sunlight, October.
• Gave an invited talk to the Bioreactors for Tissue Engineering meeting, University of Keele. November.
• Gave an invited talk, “Developing an immunocompe-tent 3D skin model for sensitization testing”, at the Colipa Skin Tolerance Workshop, Brussels, Belgium, March.
• Gave an invited talk, “Paracrine signalling communica-tion of skin cells and inflammatory detection”, to the Quasi-Vive Bioreactor Annual Meeting, Saarbrucken, Germany, May.
• Gave 3 talks at the Tissue Engineering and Regenerative Medicine International Society (TERMIS) European Chapter Grenada, Spain, July:
• “Development of a paracrine skin model for irritant detection”
• “Adipose-derived stem cells for peripheral nerve repair”
• “Polymer microfiber scaffolds for peripheral nerve repair”
• Gave 2 talks at the European Society for Biomaterials (ESB), Dublin, Ireland. September:
• “Bioengineering peripheral nerve using nerve guid-ance conduits”
• “Stem cells for nerve repair”
• Gave an invited talk, “Strategies for repairing periph-eral nerve”. to the Department of Surgery, University of Umea, Sweden. November.
• Gave an Invited talk, “Stem cells and nerve guide channels for repairing injured nerve”, to the Ludvik Boltzman Institute, Vienna, Austria, November.
• Prof John Haycock’s and Prof Nick William’s (Chemistry) work on anti-inflammatory “dip and dry” surfaces for biomaterials was featured in latest quar-terly BBSRC Business magazine as both a front cover and 2-page article. The work involved the design and synthesis of highly adhesive and self-assembling mol-ecules conjugated to anti-inflammatory peptides.
Dr John Hinton • Was awarded an Outstanding Poster Award for “The
Effect of High Temperature Grain Refinement on the Isothermal Ferrite Grain Growth Kinetics in Steel S460’ at the 4th Recrystallization and Grain Growth Conference held in Sheffield in July 2010.
• Presented a paper at the 6th International Conference on High Strength Low Alloy Steels (HSLA Steels 2011) in Beijing, China, June.
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Visiting Prof Andy Howe, in his Tata Steel role, organised and co-hosted Tata Steel’s “University Challenge” event at Warwick on 11th January 2011 with strategic partner universities (Prof Mark Rainforth representing Sheffield). Wish-lists from the company were fielded for discussion with the represented Universities to help identify topics/capabilities for short term assistance and for configuring the next round of PhD proposals.
Prof Neil Hyatt was appointed to the Chair in Radioactive Waste Management from January 2011.
Prof Beverley J Inkson• and Dr Lockwood have had an active collaboration
with Prof M S Bobji and group at the Department of Mechanical Engineering, Indian Institute of Science (IISc), Bangalore India. Research exchange visits to India in July and visits of Prof Bobji and G Vikram to Sheffield in July and September/October have been funded by a joint NanoLAB-IISc UKIERI British Council NanoBALLS project.
• Has developed collaborations with China, and hosted academic visitors Prof Yong Peng, Lanzhou University Jan-Feb 2011, and Prof Xiang Kong from the Institute of Materials for Mobile Energy, Shanghai Jiao Tong University, June.
• Organised the meeting Nanoscale Effects in Tribology, (NET 2011), Sheffield, June 2011. This meeting attracted over 50 attendees, and was supported by the EPSRC, IOM3, IMechE, IET, NanoKTN, IOP, MaterialsKTN, HealthcareKTN and Nanofactory.
• Gave an invited talk, “Squashing, sliding and melting…Real-time dynamics of moving nanomaterials”, at the In-situ Microscopy Workshop, Universität Göttingen, Germany, November 2010.
• Gave an invited talk at the Institute of Physics Workshop Small Scale Tribology, London, May.
• Prof Inkson attended the EU-funded Trends in Nanotribology conference, at the International Centre for Theoretical Physics, Trieste, Italy, September, giving a talk “Friction in action: nanoscale tribology inside electron microscopes”.
• Is a Director of the RCUK Basic Technology Research Programme in Nanorobotics.
• Is Chair of the EPSRC UK NanoFIB Network: Nanoprocessing and nanoanalysis of materials using Focused Ion Beams.
• Is Deputy-Chair of the Nanomaterials and Nanotechnology Committee of the IOMMM.
• Is a member of the EPSRC Peer Review College and also a member of the Editorial Advisory Board of the Elsevier Journal Materials Characterisation as well as a member of Scientific Programme Committee for the European Microscopy Congress (EMC 2012) and Chair of the Advances in Ion Microscopy Symposium.
• Was assessor for the German Research Foundation (DFG) and Netherlands Organisation for Scientific Research (NWO).
Emeritus Professor Frank R Jones • Is President’s invited Fellow of the Royal Aeronautical
Society (FRAeS).
• Was also invited to be Honorary Professor at Deakin University, Victoria, Australia.
• Was OCE (Office of the Chief Executive) Distinguished Visiting Scientist at CSIRO (Commonwealth Science and Industry Research Organisation) Melbourne, Australia, September 2010-May 2011, where he con-tinued his work on Self Healing Resins for use as matrices for composite materials. He was based in the Materials Science and Engineering (CMSE) labo-ratories, hosted by Dr Phil Casey and Dr Russell Varley.
• Was an invited keynote speaker at the “Carbon Fibres Workshop” organised by the Victorian Centre for Advanced Materials Manufacturing (VCAMM) and Deakin University held in Geelong. December 2010. He also gave a series of lectures:
• “Smart Self -Sensing and Self -Healing Composites”; “Molecular engineering of Interfaces and Interphases in Fibre Composites”; “From Atoms to Aeroplanes and Automobiles – Towards Multi-scale Modelling and Design of Composites”.
• Gave research seminars at the Mawson Institute of University of South Australia, Adelaide; Deakin University, Geelong; RMIT, Melbourne; Australian Composites Structures Society and Composites Research Centre (CRC), at the CRC/ DSTO laboratory in Melbourne.
Dr Plato Kapranos acted as external examiner on a PhD thesis at the Technical University of Mondragon, Spain. The theme of the work was “An investigation on the reasons behind the lack of commercial applications of semi-solid manufacturing technologies in the European automotive market, based on the factors of productivity, competitiveness, quality and cost”. Whilst there, he also spent one day carrying out experimental lab work on thixoforming low alloy steels, with his colleagues at Mondragon.
Dr Hajime Kinoshita• Completed a book chapter, “Development of ceramic
matrices for high level radioactive wastes,” for the Handbook of advanced radioactive waste conditioning technologies. The book has been published in January 2011 from Woodhead Publishing, UK.
• Was invited to give a series of lectures on the pre-dis-posal technologies for radioactive wastes at the IAEA’s training course in radioactive waste management to the participants selected by IAEA world widely, Clausthal, Germany12th-16th September.
• Gave an invited lecture, “Ceramics or cements? - Alternative cement systems and beyond” at GLOBAL 2011, 11th-16th December, Makuhari, Japan, the special focus of which was he Fukushima Daiichi accident following the devastating earthquake and consequent tsunami attacked east Japan on 11th March.
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Dr Michael Krzyzanowski• Presented on new developments related to model-
ling of FSW process at the International Conference KomPlasTech 2011 in Katowice, Poland, supported among other by ECCOMAS (European Community on Computational Methods in Applied Science). He was involved in the International Scientific Committee and presented a paper co-authored with Prof W M Rainforth.
Dr Feng Liu was chosen by the 6 participating laboratories of the European Science Foundation’s project SCALES to represent the Project at the event “Frontiers in Chemistry: From Molecules to Systems” held in Paris, 21st May with a poster entitled “Complex Mesophases and Tiling Patterns in Self-Assembled Polyphiles”. Speakers at this prestigious event included four Nobel laureates.
Prof S MacNeil• Gave the following presentations:
“Translational research in tissue engineering skin and other epithelial tissues”, Specialised Medicine Research Afternoon. Medical School, Sheffield, 13th January.
“Applications of mechanical engineering to tissue engineering”, Mechanical Engineering Research Day, Sheffield, 17th January.
“Tissue engineering –from the lab to the clinic”, Aston University, Birmingham, 4th March.
“Scaffolds for tissue engineering of skin and other epithelial tissues”, Bristol University, 11th March.
“Biomaterials for tissue engineering and wound healing”, Phillips, Eindhoven, The Netherlands, 25th March.
“3D skin models to study infection and wound healing assisted by use of bioreactors for non-invasive imaging”, 3rd Annual Quasi-Vivo User Group Meeting, Saarbrucken, Germany, 28th May.
“Biomaterials and tissue engineering for wound healing”, 1st UK-India Symposium on Materials in the Eye, Ravenhall, UK, 25th July.
“Simplifying the Transfer of Cultured Limbal Stem Cells from the Lab to the Patient”, The Cornea and Tissue Engineering, JSPS Sponsored Research Symposium, Cardiff University, 18th August.
“Biomaterials Technologies for Tissue Engineering: Scientific and Clinical Impact”, 24th European Conference on Biomaterials, European Society for Biomaterials, Dublin, 4th September.
“Biomaterials and tissue engineering for wound healing”, University of Adelaide, 10th October.
“Tissue engineering of skin and biomaterials for wound healing”, Invited talk at first annual meeting of Australian Collaborative Centre for Chronic wounds, Brisbane, 12th October.
Dr Steve Matcher• Attended Biomedical Optics, Imaging, and
Biophotonics conference (BIOS) 21st-26th 26 January in San Francisco. He gave a presentation “Optic axis determination by fibre-based polarization-sensi-tive swept-source optical coherence tomography”, and also a poster presentation, “Performance com-parison between 8 and 14 bit-depth imaging in polarization-sensitive swept-source optical coherence tomography”.
• Attended European Conferences on Biomedical Optics (ECBO) 22nd-26th May in Munich, May. He gave a presentation, “A method to calibrate phase fluc-tuation in polarization-sensitive swept-source opti-cal coherence tomography”, and also “A theoretical framework for the analysis of optical anisotropy in birefringent biological tissues with polarization-sen-sitive optical coherence tomography”. Also presented poster, “Evaluation of a swept-laser optical coherence tomography light source based on a novel quantum-dot based semiconductor optical amplifier”.
Prof Allan Matthews • Was invited to write an editorial feature on Surface
Engineering and a review article on Knowledge Transfer for “Public Service Review: UK Science and Technology” which is a pioneering publication addressing the key issues affecting the funding, appli-cation and success of the country’s science, research and technology base.
• Examined the the PhD Thesis of Xiao Ma (a former undergraduate student in the Department) at the University of Twente in The Netherlands on 11th February. The thesis title was “Surface Quality of Aluminium Extrusion Products”. He also visited the Tribology Laboratory of Prof D Schipper.
• Attended the Society of Vacuum Coaters “Techcon” Conference in Chicago USA, 16th-20th April. He partici-pated in Conference Planning Meetings and co-hosted (with Dr B Sproul) a Technology Forum Breakfast on Tribological Coatings, as well as presenting a half-day Short Course on Tribological Coatings. He was co-author (with Dr John Eichler and Dr Adrian Leyland) of the Poster Paper “A Comparative Study of Impact Testing Techniques and Results for Carbon Based Coatings”. He also co-chaired the Tribological Coatings session at the conference.
• Attended the International Conference on Metallurgical Coatings and Thin Films (ICMCTF), held in San Diego, USA, 30th April–3rd May together with PhD Students, Po-Jen Chu, Chen-Jui Liang and Omeniyi Fasuba. Their papers (co-authored with Dr Aleksey Yerokhin) were “Effect of (Poly)Phosphate Anion Structure on Characteristics of Pulsed DC PEO Coatings on Ti, for Dye Sensitised Solar Cell Applications”, “Effects of Coating Morphology on in-situ Impedance Spectra of Plasma Electrolytic Oxidation Process” and “Galvanic Corrosion Behaviour of Al-Based Coatings in 0.6M NaCl Solution”. Dr Adrian Leyland was also a co-author on the last paper. Allan and Adrian were also co-authors (with research collaborators from Tecvac Ltd) on three other papers, “An Investigation into the Effect of Triode Plasma Oxidation (TPO) on the Properties of Ti-6Al-4V”, “An Investigation into the Tribological Performance of PVD Coatings on High Thermal Conductivity Cu Alloy Substrates” and “The
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Effect of an Intermediate Electroless Ni-P Layer Prior to PVD Treatment”.
• Attended and presented an Invited Plenary paper, “Enhanced Tribo-contact Performance Using Plasma-Assisted Surface Engineering Processes”, at the 6th China International Conference on Surface Engineering in Xi’an, China, 10th-13th May. He also Chaired a Plenary session at the Conference. Whilst in China, Allan visited Yanshan University in Qiuhuangdao, where he met Prof Yulin Yang, the Vice-President (who is one of Allan’s former PhD Students) and his colleagues.
• Presented a paper, “Plasma-Based Surface Engineering for Automotive Applications”, at the IMechE Conference “Are you Slip-Sliding Away Your Profits?” The conference was held at the University of Leeds on 11th April.
• Was awarded the Gold Medal at the IOM3 Premier Awards Dinner, at Carlton House Terrace, 12th July. The award is given for a company, team or individual who has made a significant contribution to the industrial application of materials. During his 35-year career in surface engineering, he has been instrumental in transferring laboratory-based technologies to indus-try. Prof Matthews established the UK Research Centre in Surface Engineering, which has developed coatings and surface treatments that are widely used in industry. His pioneering research on envi-ronmentally friendly plasma assisted vacuum depo-sition processes has prolonged the lives of cutting tools and improved productivity. He has pioneered vacuum plasma processes for the aerospace industry. Matthews’ work on plasma electrolytic deposition techniques has application in prosthetics and light-weight vehicle structures.
• Presented a talk, “Industry Trends and Growing Markets in the UK”, at the Surface Engineering Association’s Annual Conference, in Meriden, 14th October.
• Spoke at “Functional Surfaces”, an IoP sponsored Seminar in Leeds, 14th November. The title of the talk was “Enhancing Surface Functionality by Using Nanocomposite Coatings”.
Dr Guenter Möbus• Gave an invited Departmental Seminar, “3D Imaging
of Nanoobjects: time and energy resolved electron microscopy”, at the University of Exeter, Department of Physics, 11th March 2011.
• Organised, together with the Royal Microscopical Society (RMS), the two-day workshop TEM & TOM III, 11th-12th April 2011, in Sheffield, Mappin Hall, including 4 presentations by group members Dr T Gnanavel, Dr U Bhatta, Dr W Guan, and Dr J Ghatak.
• Attended, on invitation, the workshop on “Current topics in TEM: Tomography and Plasmonics” in Tegernsee, Germany from 27th-29th July 2011, and gave an invited talk about “Model based atomic resolution (and some other) tomographies”.
• Chaired a session on “Advances in imaging and spec-troscopy” at the Electron Microscopy and Analysis Group conference of the Institute of Physics (EMAG2011) in Birmingham, 5th-9th September 2011,
including 3 papers presented by group members Dr T Gnanavel, Dr W Guan and Dr U Bhatta.
Attended the Microscopy Conference (MC2011) of the German Society for Electron Microscopy in Kiel, Germany, 29th Aug. – 2nd Sept 2011 and presented 3 papers:
“Tomographic Nanofabrication with electron beams”.
“Differential tilt between two specimen parts by an all piezo-electric miniaturised goniometer”.
“Aberration corrected TEM of irradiation induced atomic hopping processes on various ceria surfaces onserved in-situ”.
Dr Krzysztof Muszka• Attended the SIMULIA UK Regional Users’ Meeting in
Crewe.
• Co-presented an “Overview of Strain Path Effects” (co-authors B P Wynne, E J Palmiere, W M Rainforth) at Tata Research Seminar, Swindon Technology Centre, Rotherham.
• Presented a paper, “Influence of strain path changes on microstructure inhomegeneity and mechanical behaviour of wire drawing products” at the 7th Pacific Rim International Conference on Advanced Materials and Processing, PRICM, Cairns, Australia.
• Presented a paper at the 13th International Conference on Metal Forming 2012 in Toyohashi, Japan.
• Presented a paper, “Multiscale modelling of the mechanical response of dislocation structures devel-oped using high straining at low deformation temper-atures”, at TMS 2011, Annual Meeting and Exhibition in Sand Diego, USA.
• Presented a paper at the 6th International Conference on High Strength Low Alloy Steels HSLA’2011 in Beijing, China.
Prof John Parker • Attended a conference in Accra, Ghana, 15th-20th
January, jointly organised by the Association of Commonwealth Universities and British Council; in the latter case the emphasis was on AKTPs, a scheme mirroring the British Knowledge Transfer Partnerships but with African Associates.
• Was an invited guest at the Central Glass and Ceramic Research Institute (a unit of CSIR), Kolkata, India, 3rd-5th August. He also presented an invited lecture, “Modelling the optical absorption spectrum of glass” at the International Conference on Specialty Glass and Optical Fiber: Materials, Technology and Devices, ICGF-2011, organised as part of their diamond jubilee celebrations.
• Gave a plenary lecture, “Glass: colouring our view of life” at the Lomonosov International Conference on the Chemistry of Glasses and Glass-forming Melts, 4th-8th September, organised at Lady Margaret Hall, the University of Oxford by the Society of Glass Technology in celebration of the 300th anniversary of the birth of Mikhail Vasilievich Lomonosov.
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Prof Mark Rainforth• Presented the Opening Plenary, “Design of Material
Microstructure Through Optimum Processing”, at the Swedish/Indian Workshop on Advanced Materials, Kolkata, India (2011).
• Attended the Wear of Materials Conference, USA in April and presented “Wear of hydrogen free C/Cr PVD coatings” and attended the WOM Inc steering com-mittee.
• As part of his role as Visiting Professor visited Graz Technical University, June 2011 and delivered an MSc Course in the Austrian Centre for Electron Microscopy on Advanced Characterisation Techniques.
• Is Vice Chair of the forthcoming European Microscopy Congress (EMC 2012).
Prof Ian M Reaney• Gave invited talks:
“Intermediate Structures in Perovskites”, Electronic Materials and their Applications, Florida, USA.
“Planar defects and phase transitions in RE-doped Bi Ferrite ceramics”, Oak Ridge National Laboratory, STEM Group, Tennessee, USA.
“Intermediate Structures in Perovskites”, German Physical Society Meeting, Dresden, Germany.
“Planar defects and phase transitions in RE-doped Bi Ferrite ceramics”, TEM Workshop, Electron Microscopy; Exploring Materials on the Atomic Scale, Darmstadt.
“Glass ceramics and metallisations in antenna applications”, GHz Glass Ceramics Workshop, Darmstadt, Germany.
“Microwave Dielectric ceramics for mobile phone networks”, University of Birmingham Seminar Programme, Birmingham, UK.
• Was external examiner for PhD Examinations:
Rob Noble, University of Southampton, Department of Chemistry, June.
Ronald Mikkenie, University of Twente, Twente, Holland, June.
Frederic Aguesse, Imperial College, Department of Materials, December.
• Study Visits:
Department of Ceramics and Glass, University of Aveiro, April and July.
National Institute of Standards and Technology, June.
Pennsylvania State University, Pennsylvania, USA, June.
Dr Ihtesham ur Rehman• Invited talk, FTIR and Raman spectroscopy of
Biomaterials, characterisation of Advanced materials made simple, invited by Thermo Fischer at Warwick University.
• Represented the Department at the the 4th World Materials Research Institute Forum, which was held
at the Institute of Metal Research (IMR), Chinese Academy of Science, Shenyang, China. The main theme of the forum was “Materials Challenges for Safety and Reliability”, and the Symposium was divided into four topics, “Design and fabrication of high-performance materials”, “Characterization and evaluation of advanced materials”, “Property and per-formance of advanced materials” and “Applications of advanced materials”, including plenary presentations by 18 invited speakers.
• Attended Academic Council Meeting at the COMSATS University, Islamabad, Pakistan.
• Examined PhD thesis at the University of Aberdeen, Scotland.
Dr Gwen Reilly• Co-authored Poster with Jennifer E Edwards, “Low
magnitude, high frequency vibration modulates mes-enchymal progenitor differentiation”, which was pre-sented at the 57th Annual meeting of the Orthopaedic Research Society, Long Beach, California, by Jennifer Edwards.
• Co-authored Poster with Robin Delaine-Smith and Sheila Macneil, “Osteogenic media and fluid shear forces can induce osteogenic differentiation in dermal fibroblasts”, which was presented at the 57th Annual meeting of the Orthopaedic Research Society, Long Beach, California, by Robin Delaine-Smith.
• Co-authored Poster with Mohsen Shaeri, S Philips and D Athey, “Mechanical stimulation of mesenchy-mal stem cells in 3D scaffolds using oscillating fluid flow”, which was presented at the 29th Annual meeting of the Society for Physical Regulation in Biology and Medicine, Miami Beach, USA by Mohsen Shaeri.
• Gave an invited lecture, “Mechanobiology of Bone Tissue Engineering”, at the Notre Dame University in London, Workshop on Interdisciplinary Biomedical Research.
• Gave a conference oral presentation, “Cell membrane mechanosensors mediate in vitro matrix production: the role of the glycocalyx and the primary cilium”, at the University of Oxford, MediTech: Advances in Biomechanics and Mechanobiological modelling.
• Co-authored Poster with William van Grunsven and Russell Goodall, “Porous metal implants for enhanced bone in growth and stability”, which was presented at the Tissue and Cell Engineering Society UK by William van Grunsven.
• Was Publication Committee Chair of the European Society of Biomechanics.
• A member of the International Editorial Review Board of the European Cells and Materials.
Dr Conny Rodenburg• Gave an invited talk, “Energy selective secondary elec-
tron detection for the characterisation of polymer-blends”, at the Microscopy and Microanalysis confer-ence, Nashville, USA, August.
• Gave a presentation, “Energy selective secondary electron detection for the characterisation of pol-ymer-blends”, at the extraordinary seminar at the Fraunhofer Insititute for Nondestructive Testing IZFP, Dresden, Germany, August.
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Dr Alfred Sidambe Attended the Euro PM 2011 Congress and Exhibition in Powder Metallurgy in Barcelona, Spain, 9th-12th October. He presented a paper, “Fatigue Behaviour of Ti6Al4V and CP-Ti Components Processed By Metal Injection Moulding”.
Prof Derek Sinclair • Attended Zing Conference “Solid State Chemistry:
New Functional Materials, Structures and Electrical Properties” in Sharm el Sheikh, Egypt, 2nd February.
• Gave invited talks at Electronic Materials and Applications (EMA 2011, Florida) and Materials Science and Technology (MS & T 2011, Ohio). Both meetings were organised by the American Ceramic Society.
• Gave an invited seminar at the Center for Electronic Correlations and Magnetics at the University of Augsburg, Germany.
• Was also an invited guest lecturer to China in October 2011 to give a series of lectures (7 in total) on Solid State Chemistry and/or Electroceramics to Undergraduate and Postgraduate students in Xi’an (Key Laboratory of the Ministry of Education for Electronic Materials Research, Jiaotong University and The School of Material Science and Engineering, Northwestern Polytechnical University); Shenzhen (The College of Chemistry and Chemical Engineering, Shenzhen University); Shanghai (The Key Laboratory of Inorganic Coating Materials and Artificial Crystal Research Centre at the Shanghai Institute of Ceramics, Chinese Academy of Sciences); and Beijing (The College of Chemistry and Molecular Engineering, Beijing University; The Institute of Inorganic Chemistry, College of Chemistry and Molecular Engineering, Beijing University, The School of Metallurgical and Ecological Engineering, Beijing).
Dr Richard P Thackray• Was Chairman of the Iron and Steel Society of the
IOM3 and became a member of the Sustainable Development Group of the IOM3.
• Is a member of the Association for Iron and Steel Technology and a member of the World Steel University Working Group and Education and Training Committee.
• Is on the Editorial Board, Ironmaking and Steelmaking.
• Is Chair of the Organising Committee for Thermomechanical Processing Conference, TMP 2012.
• Is Secretary of the European Steel Institutes Confederation and International Society of Steel Institutes Committees.
• Chaired sessions at Waste Recovery in Ironmaking and Steelmaking, London 2011, Steel Strategy Seminar, Sheffield 2011, and the SMEA Conference, Sheffield.
Dr Karl Travis • Spent the month of August working at Swinburne
University, Australia, as a Visiting Fellow in the Department of Mathematics, Faculty of Engineering. While at Swinburne, Karl initiated 3 collaborative projects: a project involving CSIRO modelling the separation of gas mixtures using nano-engineered graphitic filters, a project aimed at understanding the existence of a liquid state and a collaboration with Applied Physics Department at RMIT on obtaining the thermal conductivity of brines at elevated tempera-ture and pressures using atomistic simulation.
• Gave two Departmental seminars, one at Swinburne, “Modelling Phase Equilibria using Dissipative Particle Dynamics”, the other at RMIT, “Configurational and Kinetic Thermostats for use in Equilibrium and non-Equilibrium Atomistic Simulations”.
• Dr Travis and James Miller attended a workshop, “Non-equilibrium Processes: The last 40 Years and the Future” held in Obergurgl, Tirol, Austria, 29th August-2nd September. Karl gave a presentation, “Fragmentation of Liquid Droplets”, while James gave a poster pres-entation, “Modeling non-equilibrium properties in nuclear waste vitrification”. The meeting was organ-ised to honour the enormous contributions made by Denis Evans in the field of non-equilibrium Statistical Mechanics and to celebrate his 60th Birthday.
• Dr Travis and Dr Henry Foxhall attended the Materials Research Society XXXV International Symposium: “Scientific Basis for Nuclear Waste Management” meeting in Buenos Aires, Argentina 2nd-7th October. Karl gave a presentation, “Deep Borehole Disposal of Higher Burn-up Spent Nuclear Fuels”, while Henry gave a presentation, “Topological analysis of accu-mulated radiation damage from multiple molecular dynamics recoil cascades”. The highlight of the meet-ing was a trip to the Atucha Nuclear Power Plant where there was a once-in-a-lifetime chance to stand inside a reactor core.
Dr Ignacio Figueroa Vargas, was named as a Runner-up for The 2009 James Clerk Maxwell Young Writers Prize for papers published during the year in Philosophical Magazine and Philosophical Magazine Letters. Ignacio was nominated by co-author, Professor Hywel Davies, for his paper, “High Glass Formability for Cu-Hf-Ti Alloys with Small Additions of Y and Si” [Ref I A Figueroa, H A Davies and I Todd, Phil Mag 89, 2355-2368 (2009).
Prof Tony West• Gave contributed talks at the Dielectrics Group meet-
ing in Canterbury in April 2011 and at the British Association for Crystal Growth conference at University College London in July.
• Was a member of the Chemistry panel that vis-ited Uppsala University in May 2011 to evaluate the University’s research in Chemistry as part of the project “Quality and Renewal 2011”.
• He was a member of the international advisory panel for the European conference on solid state chemistry, Lund, Sweden, September 2011.
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• Organised and chaired his own conference on solid state chemistry in Lanzarote, February 2012.
• He gave a plenary lecture at the European meeting on ferroelectrics, Bordeaux, France, June 2011 and organ-ised a session at the Institute of Physics dielectrics conference, Canterbury, April 2011.
Emeritus Professor Peter Wright was awarded the “Galileo Galilei Award for Energy Conversion by Ion Conduction” at the 12th International Symposium on Polymer Electrolytes (ISPE-12) in Padua, Italy. This is a new “Galileo Galilei” award.
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11 Retired Academic Staff Profiles
Prof Michael Cable
BScTech PhD DScTech TkDhc HonFSGT
Emeritus Professor of Glass Technology
Current projects concern the history of glass technology as revealed by authorities of earlier times. Five books, three translated from French or German, covering the period from 1662 to 1868 have been published. The translation of the sixth, a long book by Eberhard Zschimmer, one of Schott’s early scientific collaborators, (which Schott suppressed on its publication in 1912) is nearing completion. The seventh, a reprint of Rosenhain’s “Glass Manufacture” of 1918, is also completed.
Prof Hywel A Davies
BSc PhD ARSM DIC CEng CPhys MInstP FIMMM FREng
Emeritus Professor of Physical Metallurgy and Magnetic Materials
Research has concentrated mainly on the science and technology of solidification at ultra high cooling rates. The areas covered include: (i) the mechanisms of formation of metastable microstructures, with particular emphasis on amorphous and nanostructured alloys; (ii) the structures, properties and development of several classes of materials, including metallic glasses, novel nanophase hard and soft magnetic alloys and microcrystalline ferrous and non-ferrous alloys; (iii) the principles and applications of rapid solidification processing of advanced alloys, including the direct casting of thin strip and wire and powder atomisation followed by consolidation.
Prof Fergus G F Gibb
BSc PhD FGS
Emeritus Professor of Petrology and Geochemistry
Main areas of research interest are in geological materials (minerals and rocks) and the geological disposal of radioactive wastes, including advising the Government through membership of the Committee on Radioactive Waste Management (CoRWM). Current research is concerned principally with the concept of very deep borehole disposal which he pioneered and is now the focus of an international research consortium involving Sheffield. This concept is an alternative to mined repositories for the disposal of spent nuclear fuels and other high-level wastes and is currently attracting considerable interest, notably in the USA. Specific research activities in the context of this work are high temperature and pressure experimental mineralogy (especially nucleation, crystal growth & reaction kinetics) and modelling heat flow and related effects in and around deep borehole disposals of heat-generating radioactive wastes. A career-long interest in the mineralogy and petrology of igneous rocks, particularly geochemical processes relating to the origins of basic/ultrabasic intrusions led to recognition as an international authority on the petrogenesis of basic sills and election to Fellowship of the Mineralogical Society of America.
Prof Geoffrey W Greenwood
BSc PhD DMet CPhys CEng FIMMM FInstP FREng FRS
Emeritus Professor
Interests are centred on atomic movements, especially in relation to microstructure and to the flux paths under mechanical, chemical and thermal driving forces. The applications relate to microstructural evolution, properties of interfaces and transitions between different modes of deformation and fracture.
Prof Andy Howe
MA PhD FIMMM CEng
Visiting Professor, Tata Steel plc
Research interests cover microstructural evolution in steels including solidification and microsegregation, solid state phase transformation and recrystallisation. Current research includes the streamlined modelling of solidification at the micro-scale for coupling with macro-models, and the development of ultra-high strength steels.
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Prof Frank R Jones
PhD FIMMM CEng FRSC CChem, CSci
Emeritus Professor of Polymers and Fibre Composites
Research centres around correlations between molecular aspects and macroproperties of polymer matrix composites using micromechanical and surface analytical techniques. He has extensive research programmes on interfacial molecular engineering using plasma polymerisation; development of phase-stepping photoelastic techniques for quantifying adhesion; environmental effects specifically mechanisms of moisture absorption and thermal and hygrothermal degradation of advanced high temperature matrix systems. Group Interaction modelling of resin properties for understanding the durability of a composite from a full knowledge of the matrix performance.
Prof Howard Jones
BSc PhD CEng FIMMM
Emeritus Professor of Metallurgy and Materials
Research interests include mechanisms and modelling of solidification in general and especially, the mechanism of dendritic and eutectic growth in alloys. He has a longstanding interest in the high temperature behaviour of materials, in particular the stability of microstructure and mechanical properties. Other areas of interest include: consolidation of particulate rapidly solidified materials, together with the development of intermetallics as engineering materials, the fundamentals of ceramic/metal bonding, metallic matrix composites and wettability studies.
Dr Michael I Ojovan
MSc PhD DSc FRANS FMRS MSGT
Reader in Materials Science and Waste Immobilisation
Research interests focus on physics of metastable states, structure and properties of disordered systems and Rydberg matter, radiation-induced effects in solids. Recent work has included analysis of durability and long term performance of nuclear waste immobilising glasses and glass-composite materials, development of nuclear waste processing techniques including thermochemical decontamination and self-sustaining immobilisation.
Prof John M Parker
MA PhD FIMMM CEng FSGT
Emeritus Professor of Glass Science and Engineering
Research has included a number of themes based around structure, crystallisation and optical properties. Current major topics are glass colour and how specific ions can act as probes for local structure associated with segregation such as complex formation or fictive temperature behaviour. A particular interest is the modelling of absorption spectra as an aid to composition design for glass makers particularly when using high fractions of recycled glass. An ongoing interest is how the formation of nanocrystals within a matrix can influence the environment of dopant ions and produce specific optical effects.
Prof Thomas Schrefl
DI Dr Techn
Professor of Functional Materials
His expertise is in materials and device modelling using finite element and fast boundary element methods. The primary goal of his modelling is to obtain a better understanding of the influence of the microstructure on the properties of the materials and the application of this knowledge to simulate the functional behaviour of devices over multiple length scales. Current research includes: the simulation of hard disk recording, finite element micromagnetics, nanostructured magnetic materials, spin electronic devices, magnetic memories (MRAM), and magneto-elastic sensors.
Prof C Michael Sellars
BMet PhD DMet HonCMechD FREng FNAE (India) FIMMM
Emeritus Professor of Metallurgy
Current research interests centre on thermomechanical processing of metals and alloys, with emphasis on the microstructural changes produced and their effects on properties. The work is based on basic laboratory studies using plane strain compression testing, laboratory scale rolling, extrusion and forging, which have been used to provide data required to develop computer models of microstructural evolution and to validate the predictions of the models. Experimental studies have been carried out on a wide range of alloys including high strength low alloy (HSLA) steels, stainless steels, aluminium alloys, nickel-based superalloys, IF steels and iron aluminides.
Materials@Sheffield 2012
80 Materials Science & Engineering, The University of Sheffield
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Prof John H Sharp
BSc PhD CEng FIMMM
Emeritus Professor of Ceramic Science
Major on-going interest is in the chemistry of cements. Current topics include the hydration reactions and durability of Portland cement and composite cements (involving the partial replacement of Portland cement by waste materials or mineral products) used for nuclear waste management, and durability studies into the formation of delayed ettringite and thaumasite in Portland cement systems. In particular, the effects of pH, temperature and carbon dioxide on the thaumasite form of sulfate attack.
Prof Peter V Wright
BSc MSc PhD
Emeritus Professor of Polymers
Best known as the inventor in the mid-1970s of polymer electrolytes. His main research activities are now involved with electroactive polymeric materials, particularly low dimensional crystalline and liquid-crystalline systems with enhanced conductivities. Another major area of research is the development of novel ‘large-area’ polymer films with switchable impedances, in particular for the control of microwave transmission (“microwave smart windows”). Other areas of interest include: the interaction of ions with water soluble polymers in aqueous solutions and ring-chain equilibria, particularly in polysiloxane systems.
Department Of Materials Science & Engineering.
Materials @ Sheffield 2012.
Departm
ent of Materials S
cience & Engineering M
aterials @ S
heffield 2012
Materials Science and EngineeringThe University of SheffieldSir Robert Hadfield BuildingMappin StreetSheffield S1 3JDUnited Kingdom
Tel: +44 (0)114 222 5941Fax: +44 (0)114 222 5943
www.shef.ac.uk/materials
Every effort has been made to ensure the accuracy of the information given in this publication. However, the university reserves the right to make changes. D
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