Sintering and properties of Ultra High Temperature Ceramics for aerospace applications

The Ultra High Temperature Ceramics(UHTCs) represent a very interesting family of materials and therefore they are the subject of increasing attention from different engineeringsectors and notably the aerospace industry. Indeed, hypersonic flights, re-entry vehicles, propulsion applications and so on, require new materials that can perform in oxidizing or corrosive atmospheres at temperatures higher than 2000°C and sometimes, for long life-time. To fulfil these requirements, UHTCs seems to be one of the most promising candidates and among this family, ZrB2 and HfB2 based composites are the most attractive. Thus, in diborides-based compounds, at temperatures above 1600°C, the oxidation resistance is generally much better than that of traditional SiC-based ceramics thanks to the formation of multi-oxide scales composed of a refractory oxide (skeleton) and a glass component.