Vienna (TU). - Material scientists are developing composites which are made of dissimilar materials in order to be able to offer new customised application profiles. Researchers at the Vienna University of Technology (TU) have examined promising metal-matrix composites, which are very good conductors of heat and are able to withstand mechanical loads at elevated temperatures of up to 550 degrees and expand only very little with increasing temperature. These material combinations may be used in the ITER nuclear reactor, which is currently being constructed at Cadarache, France, and where they are intended to be used in cooling the first wall of the experimental reactor. Enhanced heat removal is playing an increasingly important role in the field of power electronics for engines and computers. Unless excess heat can be dissipated, the power of computers can no longer be increased. Last but not least, metal matrix composites can be used as cooling materials in rocket engines.
Four TU institutes are working on material combinations as part of an EU project of the 6th Framework Programme called ExtreMat (
By using simulation calculations, both the internal stresses and the thermal conductivity were predicted for given internal arrangements of composites. The Austrian company PLANSEE could set up industrial production for these new materials. “During our investigations with a synchrotron, a particularly brilliant X-ray source, in Grenoble we were able to see how the composites’ components, which are arranged three-dimensionally, deformed in different ways upon being repeatedly heated up and cooled down. Furthermore, we were able to ascertain the point at which debonds on the interface between metal matrix and diamond particles become visible in micro-tomography. These debonds are a consequence of local tensile stresses during changes in temperature. The conducting bond to the cooling plate was produced using a new coating procedure", says Degischer.
Chemists (Ass. Prof. C. Edtmaier), physicists (Prof. C. Eisenmenger-Sittner), micro-mechanicists (Prof. H. Böhm) and material scientists from the TU collaborated with two Austrian partners and 35 other European research institutes and companies on the research project “ExtreMat”. Four doctoral students successfully carried out the scientific work for the project part on behalf of the TU. Almost 1 million euro has been spent on the project over the past 4 years, 50 percent of which was financed by the European Commission.
Please direct queries to:
Prof. H. Peter Degischer
Institute of Material Science and
Vienna University of Technology
Karlsplatz 13, 1040 Vienna
T +43/1/58801 - 30801
F +43/1/58801 - 30899
Daniela Hallegger, M.A.
TU Vienna – PR and Communication
Operngasse 11/E011, A-1040 Vienna