DFG Research Training Group 1229 “Stable and Metastable Multi‐Phase Systems for Elevated Service Temperatures”

Abstract

In this Special Section, nine papers from the German Research Foundation (DFG) Research Training Group 1229 “Stable and Metastable Multi-Phase Systems for Elevated Service Temperatures” have been collected. High-temperature materials are of extremely high technical and economic interest. They play a major role in engines for transportation and energy conversion. The materials and coatings used at elevated temperatures typically are nanoscaled multiphase or composite materials with complex microstructures. The main research idea of this graduate school is to combine research activities on different classes of materials like metals, ceramics, and metal–ceramic composites for applications at high temperatures and to derive common aspects and synergies between these typically separated fields. Correspondingly, the research program of the graduate school is divided into four fields: ceramics and composites, metallic alloys, oxidation and coatings, and new methods and simulations. In total, 14 projects were funded in two rounds over a total time period of 10 years with a total financial sum of close to 10 Mio € by the DFG. Etched γ′ microstructure of a Co-based superalloy (upper left) and 2D plane weave carbon fiber reinforced ceramic matrix composite (lower left). The research training group is a joint initiative between the Universities in Bayreuth and Erlangen, which are situated within close proximity in northern Bavaria. Both universities have a high expertise in materials science and engineering, and this research program has led to a strong intensification of cooperative research activities between both universities. Also, the interaction between students has been intensified by a joint educational program. “GradKo-Bus” with members of the research training group. The general topic of multi-phase high-temperature materials also allowed creating a very attractive educational program. Different material classes, processing techniques, analytical methods, and theoretical models have been taught to the graduate students. A number of world-wide contacts allowed the incorporation of numerous well accepted international scientists within the graduate program. Many PhD students spend longer time periods abroad during a foreign research stay of up to 6 months during their PhD work at cooperating Universities like UC Berkeley, John Hopkins University, University of Cambridge, Ohio State University, University of the Witwatersrand, and many others. This was an extremely and very important element in the graduate program and helped to intensify international cooperation. A very prominent aspect of the educational program has also been the yearly summer schools, which were held at different places in the nice Franconian surrounding. The summer schools were supported by the members of the industrial advisory board, which allowed strengthening the background with respect to industrial application. During a last summer school in Heiligenstadt, we will celebrate finalizing our joint research program in July 2015. The research results have been published over the years in more than 200 publications in international journals and conference proceedings. The nine papers of this AEM volume summarize some recent results of our research training group from different fields. In this volume, several papers cover new aspects in the field of superalloy development including oxidation, TCP phase formation, phase field modeling, and other topics. Two other papers describe new developments in the field of composite materials. Members of the Research training group with external guests from the University of Cambridge during the summer school 2011 at the Castle in Pommersfelden. Mathias Göken (left) and Uwe Glatzel joint chairmen of the research training group 1229. Mathias Göken Friedrich-Alexander-University Erlangen-Nürnberg Uwe Glatzel University Bayreuth