SuperHi
Table of contents
SuperHi: Refractory metal alloys as innovative brazes for ceramic-based composites in high temperature applications
| Project manager: | Prof. Dr.-Ing. habil. Wolfgang Lippmann |
| Contributors: | Dr.-Ing. Marion Herrmann Dipl.-Ing. Marius Lau Franziska Made |
| Duration: | 12/2015 – 03/2019 |
| Funding: | Sächsische AufbauBank |
| Funding code: | 100233245 (Antragsnummer) |
| Cooperations: |
Fraunhofer IKTS Dresden, Dr. Hans-Peter Martin |
Brief Description
The aim of the applied research project is the development of braze systems for the joining of ceramic materials (SiC, Al2O3, ZrO2) for use under conditions of high thermal stress of the joint (temperatures ≥ 1,600 °C).
Here, for selected systems of refractory metals (Ta, Zr, W, Ti, Ni), the state of the art with regard to phase formation, microstructure and wettability with ceramics and other refractory metals will be expanded. For example in figure 1, a cross section of a joint between SiC with a NiTa is following. The braze joint consists of a braze metal zone of NiSi which is surrounded by a brighter transition zone of TaC.
Figure 1: Light micrographs of silicon carbide left in the polished state and right in the con-trasted state.
With these results, braze systems have to be developed whose ductility, strength and high-temperature resistance are superior to previously known braze systems. In this case, chemical interaction between braze metal zone and the substrate material during subsequent thermal use should be minimized, so that the technical usability is not impaired. The target temperature for an application of the bonded composites is
1,600 °C.