F R A U N H O F E R I N s T I T U T E F O R P R O d U C T I O N T E C H N O l O g y I P T

Turning processes – new compacT process chains and combinaTions

High-precision hard turning & honing / High-precision

hard turning & polishing

For many applications, hard turning provides an interesting

alternative to grinding techniques. Advantages that are spe-

cific to the process, such as short set-up times, dry processing

capabilities and a high degree of flexibility, make hard turning

techniques relevant, not only for the conventional field of

individual products and small series production but also for

mass production applications.

Most machining is performed on hard and hardened steels

as well as cemented carbides. The range of products consists

of bearing components, pneumatic and hydraulic parts and

chip-free forming tools. By optimizing the process (in terms of

cutting material, process parameters, machining strategy) to

improve the results, it becomes possible to achieve accuracies

from IT3 to IT5 and surface qualities Rz of less than 1 µm.

The combinations of hard turning/honing and hard turning/

polishing developed by the Fraunhofer IPT achieve surface

roughness values of up to optical qualities (Ra < 20 nm).

The Fraunhofer IPT develops ideas and solut ions for new combinat ions and chains of processes involv ing

turning. By combining honing and pol ishing with hard turning, i t becomes poss ib le to apply the technol-

ogy in new ways to hard and hardened steels and cemented carbides to achieve opt ica l surfaces. When

high-performance turning is combined with 5-axis mi l l ing, i t becomes poss ib le to process even hard to

machine mater ia ls without a machine change.

The aim of our research is to produce components with better to lerances and surface qual i t ies in less

t ime. This i s achieved by integrat ing the aforementioned process combinat ions into one lathe, which a lso

makes i t poss ib le to machine the workpiece without the need for re-c lamping.

High-performance turning

Only materials like titanium alloys, titanium aluminides and

nickel-based alloys are used in the manufacture of compo-

nents for turbo-engine applications – all materials with low

thermal conductivity and high heat-resistance that are hard to

machine. Over the last few years, the Fraunhofer IPT has built

up outstanding expertise in the 5-axis milling of these materi-

als. The analysis and optimization of NC data are essential

here – including the continuous analysis of the kinematic and

dynamic properties of the machines and controls.

We transfer the available knowledge to the turning process

and optimize the combination of turning/5-axis milling for

the manufacture of turbo engine components. The ability to

process such components in just one machine also eliminates

long, unproductive periods due to machine changes.

advanTages of Turning process combinaTions

Our offer

In our approach to technology-oriented process design,

we combine technological knowledge and experience with

manufacturing-orientated technology assessment. We help

you to improve your production processes and process chains

in terms of technical and economic criteria.

Our range of services in the field of turning includes

• Processing trials

• Feasibility studies

• Technology development

• Process development, process design and process optimization

• Manufacture of prototypes and small sized batches

• Help for industrial-scale implementation

Sophisticated equipment in conjunction with comprehensive

measuring and analysis facilities and software tools enables

the Fraunhofer IPT to process and evaluate complex, high-

precision components made of almost any material:

• Hard and hardened steels

• Cemented carbides

• Titanium and titanium alloys

• Nickel-based alloys

• Non-ferrous metals

We can machine components ranging from the smallest chuck

components to parts of up to 1 000 mm in diameter and

1 500 mm in length.

Our machining equipment

Three high-precision hard turning lathes (Hembrug)

• Slantbed on natural granite base

• External electric and hydraulic supply unit

• Integrated temperature-controlled coolant supply

• Hydrostatic bearings for spindle and support

• Spindle run-out accuracy < 0.1 µm

• Repeatability accuracy < ± 0.1 µm/150 mm

• Positioning accuracy < 0.1 µm/150 mm

• Integrated honing device (Hembrug 50 CNC)

• Integrated polishing spindle (Hembrug 100 CNC)

Monforts Unicen 1000 Multiturn

• Swing

– above bed 1 000 mm

– above cross slide 800 mm

• Machinable length 1 500 mm

• Compound slide rest X, Z and Y axis

• Interpolating B-axis

• Head with holder for static and powered tools

• Tool magazine (chain magazine) for 34 tools

• High-pressure cooling at 350 bar

• Tool and part measurement system

• Main and opposed spindle

Fraunhofer Institute for

Production Technology IPT

Steinbachstrasse 17

52074 Aachen

Germany

Phone +49 241 8904-0

Fax +49 241 8904-198

info@ipt.fraunhofer.de

www.ipt.fraunhofer.de

Contact

Dr.-Ing. Thomas Bergs

Phone +49 241 8904-105

Fax +49 241 8904-6105

thomas.bergs@ipt.fraunhofer.de

Dipl.-Ing. Jens Helbig

Phone +49 241 8904-136

Fax +49 241 8904-6136

jens.helbig@ipt.fraunhofer.de