Post on 27-Jan-2021
VIZ GRAF, Busteni, October 2006 1
RESULTS AND TRENDS RESULTS AND TRENDS IN THE DEVELOPMENT OF IN THE DEVELOPMENT OF
NANOCOMPOSITE NANOCOMPOSITE MATERIALSMATERIALS
Radu L. OrbanRadu L. Orban
Technical University of ClujTechnical University of Cluj--NapocaNapocaROMANIAROMANIA
VIZ GRAF, Busteni, October 2006 2
Nanocomposite materials Nanocomposite materials iinspired from the naturenspired from the nature
BBiological materials join together:iological materials join together:-- sensingsensing-- actuation actuation -- healinghealing-- other propertiesother properties
built into the primary built into the primary structurestructureof an organismof an organism
Extension to materials design :Extension to materials design :-- mechanicalmechanical-- electricalelectrical-- electronicelectronic-- magneticmagnetic-- optical, etc. optical, etc.
integrated functionsintegrated functions
VIZ GRAF, Busteni, October 2006 3
How to get these integrated functions ?How to get these integrated functions ?combining combining metallic, ceramic, polymericmetallic, ceramic, polymeric materials to a :materials to a :
-- nanometricnanometric-- molecularmolecular-- atomicatomic
| scalescale to work in synergyto work in synergyExpected properties :Expected properties :
beyond those of the sum of individual capabilitiesbeyond those of the sum of individual capabilities
incorporated intelligenceincorporated intelligence high added valuehigh added value
The new, as obtained, The new, as obtained, nanocomposite materialsnanocomposite materials | IntermaterialsIntermaterials
VIZ GRAF, Busteni, October 2006 4
PossibilitiesPossibilitiesto obtain nanocomposite structures to obtain nanocomposite structures Intra-type
High strength and reliability, Excellent HT High strength and reliability, Excellent HT mechanical properties, High toughnessmechanical properties, High toughness
Super tough and strong(at room and high temperatures)
Micro/Nano Hybrid - type Mutual Nano - type
Micro - sized particles,whisker or fibers
Phase A Phase B(A/B + B/A)
New functions:New functions:MachinabilityMachinability
SuperplasticitySuperplasticity
Inter-type Intra/Inter-type Nano/Nano-type
Nano dispersion
Intra-type
K. Niihara, 4th International PM Conference of Turkey, Sakarya 2005
VIZ GRAF, Busteni, October 2006 5
Common Bulk Nanocomposites
Strongly improved mechanical properties
Metal/Ceramic/PolymerMetal/Ceramic/Polymer--Ceramic/Metal Ceramic/Metal
SystemsSystems
Structural MaterialsStructural Materials
Nanoparticles
Micro Matrix
Ceramic-Pores Nanocomposites
Permeability, High Fracture Toughness, Strength
CeramicCeramic--Nanopores SystemsNanopores Systems
Metal/Ceramic-Carbon Nanocomposites
Metal/CeramicMetal/Ceramic––Carbon SystemsCarbon Systems
Hard/Soft Nanocomposites
Mechanical Properties, Machinability
CeramicCeramic--Metal, CeramicMetal, Ceramic--CeramicCeramicSystemsSystems
Micro/Nano Composites
Nano Sized2nd Phase
Matrix
High Fracture Toughness, Strength
MetalMetal--Ceramic, CeramicCeramic, Ceramic--Metal, Metal, CeramicCeramic--Ceramic SystemsCeramic Systems
In-grain toughening
Micro Sized2nd Phase
Carbon Nanotubes/Fullerenes
Matrix
Soft 2nd Phase
Hard Matrix
Novel Nano Processing
Nanopores
Matrix
Grain BoundaryControl Concept
Polymer Based Polymer Based NanocompositesNanocomposites
Metal Based Metal Based NanocompositesNanocomposites
Ceramic based Ceramic based NanocompositesNanocomposites
High Strength, Fracture Toughness
micro/nano
Bulk Nanocomposite MaterialsBulk Nanocomposite Materials
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Recent achievements Recent achievements in nanocomposites developmentsin nanocomposites developments
⎪⎪
Common Metal Matrix Nanocomposites (MMNCs)*
Modern method of MMNCs production:
InIn--situ reactive synthesis situ reactive synthesis of reinforcing phases in the metalof reinforcing phases in the metalmatrix melt / powder compactsmatrix melt / powder compacts
-- Reinforcing particles:Reinforcing particles:-- nanometric size nanometric size -- thermodynamically stable, thermodynamically stable, -- uniformly distributeduniformly distributed
-- Cleaner interfacesCleaner interfaces-- Energy savingsEnergy savings
Matrix materials : Matrix materials : Al, Ti, Ni, Cu, Fe, various alloysAl, Ti, Ni, Cu, Fe, various alloys
Reinforcing phases : Reinforcing phases : oxides, carbides, borides, nitridesoxides, carbides, borides, nitrides
VIZ GRAF, Busteni, October 2006 7
Possible reactions ofPossible reactions ofMMNCs Reactive Processing* MMNCs Reactive Processing*
Synthesis reactionsSynthesis reactionskM + mR + nC kM + RmC n (1)(m+p)R +nC pR + RmCn (1’)
Displacement reactionsDisplacement reactions
MMkkTT nn + mR + mR kM + RkM + RmmTTnn (2)(2)
kM + MkM + MppTTnn+mR +mR (k+p)M +R(k+p)M +RmmTTnn (2(2’’))
kM + mR + XkM + mR + XttTTn+qn+q kM + RkM + RmmTTnn + X+ XttTTq q (3)(3)
Thermodynamic condition:Thermodynamic condition: ΔΔGG00f/rf/r < 0< 0* R.L. Orban, Proceedings RoPM 2000, Cluj-Napoca
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Thermodynamic possibilities Thermodynamic possibilities of reactive processing of MMNCs*of reactive processing of MMNCs*
Oxide RCs inOxide RCs in--situ synthesissitu synthesis Carbides/Borides RCsCarbides/Borides RCsinin--situ synthesissitu synthesis
-1500
-1000
-500
0
500
1000
0 500 1000 1500 2000 2500 3000
Temperature, T [K]
Stan
dard
Gib
bs F
ree
Ener
gy o
f For
mat
ion,
ΔG
0f [k
J/m
ol]
Al + 2/3Al2O3 + Zr = 7/3Al + ZrO2Ti + 2Al + 1.5TiO2 = 2.5Ti + Al2O3Ti + Zr + TiO2 = 2Ti + ZrO2Ti + 3Al = TiAl3Ni + 2Al + 3NiO = 4Ni + Al2O3Ni + Zr + 2NiO = 3Ni + ZrO22Ni + 3Al = Ni2Al3Cu + 2Al + 3CuO = 4Cu + Al2O3Cu + Zr + 2CuO = 3Cu + ZrO2Fe + 2Al + Fe2O3 = 3Fe + Al2O3Fe + Zr +2/3 Fe2O3 = 7/3Fe + ZrO2
-350
-300
-250
-200
-150
-100
-50
0
50
100
0 500 1000 1500 2000 2500 3000 3500
Temperature, T [K]
Stan
dard
Gib
bs F
ree
Ener
gy o
f For
mat
ion,
ΔG
0 r [k
J/m
ol]
Ti + C = TiC2Ta + C = Ta2CNb + C = NbCV + C = VC4B + C = B4C4Al + 3C = Al4C33Fe + C = Fe3C3Ni + C = Ni3C3Al + Ti = Al3Ti3Ni + Ti = Ni3TiTi + 2B = TiB2Zr + 2B = ZrB2Al + 12B = AlB12Fe + B = FeB4Ni + 3B = Ni4B3
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Bulk metalsBulk metalsmultifunctionalisationmultifunctionalisationCu/Ni (~500Cu/Ni (~500 nm) + nm) + (3.3(3.3÷÷5.6) wt.% Al5.6) wt.% Al22OO33 (20 nm)(20 nm)
-- Higher mechanical strength than Cu/Ni (~1.5 x)Higher mechanical strength than Cu/Ni (~1.5 x)
-- Higher hardness / wear resistance, Higher hardness / wear resistance, endurance limit (4endurance limit (4÷÷6 x)6 x)
-- The same electrical conductivity/ The same electrical conductivity/ magnetic properties / corrosion magnetic properties / corrosion resistance as resistance as Cu / Ni pure metalsCu / Ni pure metals
Applications : Applications : -- heavy duty electrical contacts heavy duty electrical contacts -- magnetic cores for hostile environments etc.magnetic cores for hostile environments etc.
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WW--Cu nanocompositesCu nanocomposites- higher strength than similar
crystalline materials fabricated by liquid phase sintering / infiltration
- lower thermal expansion coefficient
Applications :- heavy duty heavy duty electrical contactselectrical contacts-- electrodes for electroelectrodes for electro--dischargedischarge
machining, shape charge linersmachining, shape charge linersNanocrystalline Cemented Nanocrystalline Cemented carbidescarbides very thin tools, e.g. drilling tools very thin tools, e.g. drilling tools
ØØ < 0.5 mm< 0.5 mm
3
4
5
6
7
8
9
0,05 0,1 0,15 0,2 0,25 0,3
Cu content, [wt. fraction]
CTE
, [pp
m /
K]
NanocompositeComposite by infiltration 1Composite by sinteringComposite by infiltration 2
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Nanocomposites Nanocomposites (Intra&Intergranular)(Intra&Intergranular)
Notable enhancement of:Notable enhancement of:-- Mechanical Mechanical and thermal propertiesand thermal properties
-- Homogeneity atHomogeneity atthe nanoscalethe nanoscale
-- Physical andPhysical andchemical propertieschemical properties
Addition of new functionsAddition of new functionsGradual components Gradual components dispersion dispersion FGMFGM
Monolithic and/or Monolithic and/or MicroMicro--compositescomposites
- Mechanical properties are notenough high e.g. toughness
- Inhomogeneity ofmicrostructure, mechanical,physical properties
Bulk nanocrystalline ceramicsBulk nanocrystalline ceramicsNecessity of further Necessity of further improvements / improvements / multifunctionalisationmultifunctionalisationStructure control at nanoStructure control at nano--scalescale
G.B. modification (Intergranular N.Cs.)
VVery small additions ery small additions of secondary phase(s)of secondary phase(s)
Homogeneity in nano and/or molecular-scalePhysical properties enhancementAddition of new functions: electric, optical, etc.Reliability enhancement
K. Niihara, Key Engineering Materials, Vols. 161-163 (1999), pp. 527-534.
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CeramicCeramic--metal nanocompositesmetal nanocompositesAl2O3 - (W, Mo, Ti, Ni, Co, Fe, FeNi)ZrO2 - (Mo, Ni. Co)MgO - (Fe, Ni)Mullite - (Ni, Co, FeCo)SiC – (Al, AlSi, AlZn, AlMg)
CeramicCeramic--ceramic ceramic
SHSSpark PlasmaSintering Two-stepsinteringElectrophoresisInfiltration
Al2O3 - (SiC, ZrO2 , TiC, TiN, TiB2, BN) MgO - SiC Si3N4 - (SiC, TiN, BN, ZrO2 ) B4C - SiC, B4C – SiC+ TiB2
IntermetallicIntermetallic--ceramic ceramic NiAl NiAl –– AlAl22OO33 –– TiBTiB2 2 * * SHS under pressure SHS under pressure
* R.L. Orban, M. Lucaci,, 16th International Plansee Seminar, Reutte, Austria 2005 High Performance PM Metals, vol. 1, p. 1170- 1180
VIZ GRAF, Busteni, October 2006 13
AlAl22OO3 3 -- SiC nanocompositeSiC nanocompositeAl2O3 monolith
Al2O3/5vol%-SiC Nanocomposite
Typical SEM Microstructure Intragranular SiC dispersion
K. Niihara, 4th International PM Conference of Turkey, Sakarya 2005
VIZ GRAF, Busteni, October 2006 14
SiSi33NN44 (SiC, Al(SiC, Al22OO33, ZrO, ZrO22) ) –– SiNSiNnanocompositenanocompositeTo improve machinability, To improve machinability,
toughnesstoughnessSi3N4/SiC/ZrO2/Al2O3 (powder)
+H3BO3
+CO(NH2)2 (urea)
Ball Milling
H2Reduction
Si3N4 nanopowder + BN precursor coating
(t-BN)
HPSintering
Si3N4//SiC/ZrO2/Al2O3 -hBN
NanocompositeK. Niihara, 4th International PM Conference of Turkey, Sakarya 2005
VIZ GRAF, Busteni, October 2006 15
4mm4mm4mm
SiSi33NN44 (SiC, Al(SiC, Al22OO33, ZrO, ZrO22) ) –– SiN SiN nanocompositenanocompositeMultifunctinality realised :
-- High strength at room and elevated temperaturesHigh strength at room and elevated temperatures
-- Higher toughnessHigher toughness-- Lower hardness and Young's ModulusLower hardness and Young's Modulus
-- QuasiQuasi--plasticityplasticity- Good machinability (>15vol%hGood machinability (>15vol%h--BNBN))-- Excellent thermal shock resistanceExcellent thermal shock resistance- Good corrosion resistance to molten metals
SiSi33NN44 –– SiC nanocompositeSiC nanocompositesuperplasticitysuperplasticity
Properties : - mutual C-CNCsStrength: 1.2 GPa (RT); 1.0 GPa (1000 oC)KIC : 8 MPam 1/2
VIZ GRAF, Busteni, October 2006 16
Bulk polymer nanocompositesBulk polymer nanocomposites
Polymer – metal nanocompositesPolymers Polymers –– metallic nanopowders (Ag, Cu, Ni, Fe, magneticmetallic nanopowders (Ag, Cu, Ni, Fe, magneticalloys) alloys) mechanical / electrical / magnetic / decorativemechanical / electrical / magnetic / decorativemultifunctionalisationmultifunctionalisation
Polymers (Polymers (thermoplastics) / Elastomers thermoplastics) / Elastomers ––metallic/ceramic nanopowders / nanotubesmetallic/ceramic nanopowders / nanotubes-- nanopowders/nanotubes nanopowders/nanotubes high specific surface area high specific surface area
difficulties in incorporation into polymer matrix difficulties in incorporation into polymer matrix surfactantssurfactants
Polymer – ceramic nanocompositesPolymers Polymers –– ceramic nanopowders (SiOceramic nanopowders (SiO22, Al, Al22OO33, clay etc.) , clay etc.) mechanical / electrical /electronic / opticalmechanical / electrical /electronic / optical multifunctionalisationmultifunctionalisation
VIZ GRAF, Busteni, October 2006 17
Polymer (pPolymer (polypropylene, nylon etc.olypropylene, nylon etc.) ) ––clay nanocompositesclay nanocomposites
Clay (Clay (montmorillonite)montmorillonite)a multilayer aluminoa multilayer alumino--silicatesilicate
-- interinter--layer layer spacing in the nanometric range spacing in the nanometric range organophobicorganophobic vs. vs. organic compounds organic compounds surfactants surfactants
organoclay organoclay delaminated delaminated layers layers ~ 1 nm thickness / high aspect ratios (10 ~ 1 nm thickness / high aspect ratios (10 ÷÷100)100)
Two types of composites Two types of composites
delaminated (exfoliated) delaminated (exfoliated) montmorillonite montmorillonite layered crystal structurelayered crystal structure
intercalatedintercalated
Properties (Nylon+5wt.% Clay)
- 68 % higher E; 126 % higher G- 60 % higher σfl; tdistorsion: 65 152 0C
VIZ GRAF, Busteni, October 2006 18
Mechanical multifunctionalisation Mechanical multifunctionalisation through Carbon nanotubesthrough Carbon nanotubes
a) Single wall SWCNT
b) Multi-wallMWCNT
7.89.00.8207Steel
2.716.00.569Aluminium
4.515.00.9103Titanium
1.61.22.1152Graphite fibre
1.81.52.71260MWCNT
1.44.065.01210SWCNT
Density(g/cm3)
Fracture Strain(%)
Yield Strength(GPa)
Elastic Modulus(GPa)Material
Mechanical properties of CNTs/common engineering materialsMechanical properties of CNTs/common engineering materials
ØØ = 2 = 2 ÷÷ 20 nm20 nmℓℓ < ~ 10 < ~ 10 μμmm
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Metal Metal –– Nanotubes nanocompositesNanotubes nanocomposites
Ceramic Ceramic –– Nanotubes NCsNanotubes NCs
Polymer Polymer –– NanotubesNanotubes NCsNCs
Nanotubes fabricationNanotubes fabrication (Ni, Fe, Co etc. catalysts) (Ni, Fe, Co) oxides + CNTs (MO-CNTs) nanocomposite powders
Ni/Fe/Co + (MO-CNTs NP) (Me + MeO + CNTs) NCs- Properties: Properties: UTS UTS 34 34 ÷÷ 37 % higher 37 % higher GearsGears
SiOSiO22 (quartz) + MWCNTs (quartz) + MWCNTs CMNCsCMNCs ((133 133 ÷÷ 146 %146 %higher toughness, preserving clarity, corrosion resistance etc.)
CNTs CNTs high flexibility high flexibility bend during bend during processing processing CNTsCNTs network interpenetrating network interpenetrating the polymer matrix the polymer matrix High mechanical resistanceHigh mechanical resistance
VIZ GRAF, Busteni, October 2006 20
Mechanical multifunctionalisationMechanical multifunctionalisationthrough through nanocomposite coatingsnanocomposite coatingsNanostructuredNanostructured coating layerscoating layers (NSCLs)(NSCLs)
Nanosized hard compounds (SiC,TiC,TiN)+Me (Al, Ni) NSCLs low friction coefficient, very high wear resistance
Nanostructured Diamond/DLC/TiN filmsNanostructured Diamond/DLC/TiN films
CrystallineCrystalline NanocrystallineNanocrystalline
Can be obtained by:Can be obtained by:- Microwave plasma enhanced CVD- Laser ablation of graphite
Results: spsp33 hybridisationhybridisation øø10 10 ÷÷ 50 nm nodules of 50 nm nodules of diamond diamond nanocrystalline filmsnanocrystalline films smoother surfacesmoother surface11÷÷3 3 μμm thick, 80 GPa hardness, low friction coefficientm thick, 80 GPa hardness, low friction coefficient
VIZ GRAF, Busteni, October 2006 21
Multifunctionalisation Multifunctionalisation through nanoporesthrough nanopores
Nanopore creationNanopore creation new properties, keeping / new properties, keeping / enhancing the initial ones enhancing the initial ones multifunctionalisationmultifunctionalisationCore material+nanoporesCore material+nanopores nanostructured nanostructured
materialmaterialNanopores creation :Nanopores creation :-- nanoporous Carbon structuresnanoporous Carbon structures-- ceramic nanoporous materialsceramic nanoporous materials
Nanoporous Nanoporous Carbon Carbon
structuresstructuresNanoporous carbon + Metal particles Nanoporous carbon + Metal particles catalyst materials*catalyst materials*
*L. Gray et al., Wiley, 2005.
VIZ GRAF, Busteni, October 2006 22
BCNs infiltrationBCNs infiltration bulk nanocomposite materialsbulk nanocomposite materialsProcessed by solProcessed by sol--gel method in the gel method in the ““aeroaero--gelgel”” variantvariant
Ceramic nanoporous materialsCeramic nanoporous materialsBlock ceramic materials (BCNs) Block ceramic materials (BCNs)
Nanostructured ceramic membranes (NCMs)Nanostructured ceramic membranes (NCMs)Commonly made from SiO2, Al2O3, TiO2 and ZrO2
- pores diameter: 3÷ 5 nm
Processing by Aerogel methodProcessing by Aerogel methodlike block nanoporous ceramicslike block nanoporous ceramics
Producing by SelfProducing by Self--assembly assembly method method templatetemplate--assisted assisted selfself--assemblyassembly like biological systemslike biological systems
VIZ GRAF, Busteni, October 2006 23
SuperconductiveSuperconductiveceramicsceramics
Ionic conductive ceramicsIonic conductive ceramics
Ionic carriers transport Ionic carriers transport by diffusionby diffusionNernst Nernst –– Einstein equation:Einstein equation:
σi = Di . Ni . Qi / k . T- σi electrical conductivity- Di diffusion coefficient of “ i ” specie- Qi electrical charge- Ni charge carrier concentration- k Boltzman constant
- T absolute temperature
σi = ƒ(Di)
VIZ GRAF, Busteni, October 2006 24
Electrical SuperconductiveElectrical SuperconductiveCeramics by Grain Boundary ControlCeramics by Grain Boundary ControlDigb>> Div σigb >> σiv
Ionic superconductive ceramicsIonic superconductive ceramicsSi3N4 / E2O - Al2O3- SiO2
(E = Na, Li, K, etc) MgO / Na2O - Al2O3- SiO2
Electronic superconductive ceramicsElectronic superconductive ceramicsZrO2 / V2O5 - Bi2O3 - CuO AlN / YN, etc.
GB conduction
mainly at hightemperature
GB + latticeconduction
at roomtemperature
VIZ GRAF, Busteni, October 2006 25
Ionic superconductiveIonic superconductiveceramicsceramics
~ 5 x 102 at 1000 0C107Mullite / Na2O-Al2O3-SiO2
~ 102 at 1000˚C106~107 at 100˚CDMgO / Na2O-Al2O3-SiO2
~ 5 x 101 at 1000 0C107~ 108 at 100 0C1010Si3N4 / Li2O-Al2O3-SiO2
~ 8 x 101 at 1000 0C107~ 107 at 100 0C1010Si3N4 / Na2O-Al2O3-SiO2
Resistivity [Ω.cm-1]NanocompositeMonolithMaterial
Ionic conductive
VIZ GRAF, Busteni, October 2006 26
ConductivPass-way
Electronic grain boundary Electronic grain boundary conduction in ceramicsconduction in ceramics
500nm
AlN
AlN
Grain boundary phase
AlN
Grain boundary phaseAlN
Electronic conductivity through pass-way of grain boundaries
Schematic model of conduction in Schematic model of conduction in AlN/Y2O3AlN/Y2O3--CeO2CeO2nanoconanocompositesmposites
VIZ GRAF, Busteni, October 2006 27
Electronic superconductiveElectronic superconductiveceramicsceramics
~10-1 at T1014Y-TZP/CNT
~108 at R T1012Al2O3 / TZP+CNT Hybrid
~ 10-1 at RT (AC) 1010Si3N4 / V2O5 System
~ 2 x10-1 at RT1011AlN / YN System
~ 102 at RT1014Y-TZP / Organic System
~ 102 at RT1014Y-TZP / Bi2O3-CuO-V2O5
Resistivity [Ω.cm-1]NanocompositeMonolithMaterial
Electronic conductive
VIZ GRAF, Busteni, October 2006 28
Polymer electricalPolymer electricalmultifunctionalisationmultifunctionalisation
Purpose :Purpose :To get higher conductivity than common To get higher conductivity than common
conductive polymers & higher strengthconductive polymers & higher strength-- by high conductive metal particles by high conductive metal particles
(Cu, Ag, Au) fillers (Cu, Ag, Au) fillers percolation threshold percolation threshold controlled / unidirectional conductioncontrolled / unidirectional conduction
To get special properties To get special properties magnetic (e.g. nano Ni filler), magnetic (e.g. nano Ni filler), electronic, optical,electronic, optical,shape memory effectsshape memory effects
VIZ GRAF, Busteni, October 2006 29
Shape memory effect inShape memory effect innanocomposite polymersnanocomposite polymers(artificial muscles(artificial muscles))
Ionic PolymerIonic Polymer-- metal nanocompositesmetal nanocomposites- Elecyroactive polymers per fluorinated ionomers Polyperfluoroethilenesulfonate, e.g. Nafion, Fluolon etc.
-- Applied electric field Applied electric field generation generation of cations of cations migration toward cathod migration toward cathod
pressure pressure reversible bending reversible bending 10 x higher than shape memory 10 x higher than shape memory alloys (e.g. Nialon)alloys (e.g. Nialon)
Mechanism :Mechanism :
Applications:Applications: actuators, medical devices etc.
VIZ GRAF, Busteni, October 2006 30
ElectricalElectricalmultifunctionalisation multifunctionalisation of materials with CNTsof materials with CNTs
Electrical/electronic properties of CNTsElectrical/electronic properties of CNTs- One dimensionalityOne dimensionality 1 D space 1 D space electrons confined electrons confined
in one direction in one direction ideal 1 D conductors / semiconductors ideal 1 D conductors / semiconductors ƒƒ (cyrality (cyrality –– atom disposal in the hexagonal ray)atom disposal in the hexagonal ray)
-- BendingBending atom disposal changes cylarity change metal to semiconductor transitions nanojunctionsnanojunctions
Field Emission Transistors
- Monochromatic electron beams, emitters, nanoconnectors etc.
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ElectronicElectronicmultifunctionalisation multifunctionalisation by nanostructured coatingsby nanostructured coatingsNanocrystalline diamond coatings
Fotoluminiscence Fotoluminiscence propertiesproperties
Colors depending on Colors depending on the electron beam the electron beam intensity intensity easy to be easy to be changedchanged
High resolution, high High resolution, high dimensions displayersdimensions displayers
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OpticalOpticalmultifunctionalisationmultifunctionalisation
Strong transparent Si3N4Control the chemical composition and structure of G.B.Control the chemical composition and structure of G.B.Able to fabricate by common sintering processAble to fabricate by common sintering processHigh strength and toughnessHigh strength and toughness
400 mm 500 mm 600 mmApplications: Spatial vehicles windows
VIZ GRAF, Busteni, October 2006 33
Future trendsFuture trends
Nanocomposites
Strongly improvedmechanical properties
Ceramic/Ceramic SystemsCeramic/Ceramic Systems
Structural Materials
Nano Particle
Micro Matrix
Molecular Composites
Modified Lattice
Matrix Atom
Extremely low fraction of 2nd phases
(5 vol%, 0,01 − 0,1 vol%)Ceramic/Ceramic, Organic/Ceramic/ Ceramic/Ceramic, Organic/Ceramic/
Systems
Multifunctional Materials
Layer by LayerLayer by LayerLattices CompositesLattices Composites
≈ 1 nm(Insulators)
1 μm
Bulk multilayer structure materialCeramic/Ceramic SystemsCeramic/Ceramic Systems
Core/Shell NanoclusterComposites
Core
20 nm
Shell
Novel magnetic/electric properties
Metal/Metal, Metal/CeramicSystems
Magnetic/Optic/Electric Devices
Nanoporous Composites
2nd Phase
20 nm
MatrixNanopore
Large surface area, Improved thermal shock
resistance
Ceramic/Metal SystemsCeramic/Metal Systems
Catalysts, Coating Materials
NanoParticles
FullereneDispersed
NanoComposites
Nano Tubes
Self-Organized
NanoComposites
In-grain toughening
5 ÷ 10 nm(Ferroelectrics)
VIZ GRAF, Busteni, October 2006 34
ConclusionsConclusionsNanocomposite Nanocomposite materials open materials open
an enormous potential for :an enormous potential for :- existing materials multifunctionalisation- enhancing natural performances of
existing materials- creation of new multifunctional materials- materials designmaterials design- development of functionally-graded
materials - broad and exciting research area
VIZ GRAF, Busteni, October 2006 35
Thank you for your attention !Thank you for your attention !