Ultra High Temperature Ceramics: Densification, Properties and Thermal Stability
نویسندگان
چکیده
Hypersonic flights, re-entry vehicles, and propulsion applications all require new materials that can perform in oxidizing or corrosive atmospheres at temperatures in excess of 2000°C and sometimes over the course of a long working life. Ultra High Temperature Ceramics (UHTCs) are good candidates to fulfill these requirements. Within this family, the ZrB2 and HfB2 based composites are the most attractive. The oxidation resistance of diboride-based compounds is better than that of SiC-based ceramics thanks to the formation of multi-oxide scales composed of a refractory oxide (skeleton) and a glass component. Onera is actively involved in several programs to develop such materials for both hypersonic civilian flights and for propulsion systems.
منابع مشابه
Effect of Silicon Carbide and graphite additives on the pressureless Sintering mechanism and microstructural characteristics of Ultra-High Temperature ZrB2 Ceramics Composites
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