Development of Ultra-High Temperature Ceramics: From Monoliths to Composites

Regarding materials development, our studies have been mainly focused on ZrB2-SiC and HfB2-SiC compositions with TaSi2 or Y2O3 additions using hot pressing and spark plasma sintering. These additives have been used to decrease the sintering temperature and to improve the oxidation resistance. Interesting mechanical properties at room and high temperature have been measured. Moreover, excellent oxidation behaviors have been observed up to 2000-2200°C with Y2O3. Last developments are centered on the manufacturing of ultrahigh temperature ceramic matrix composites (UHTCMC) using slurry infiltration and pyrolysis for example. First results are encouraging.