Based on the sensitivities of material properties to temperature and the complexity of service environment of thermal protection system on the spacecraft, ultrahigh-temperature ceramics (UHTCs), which are used as thermal protection materials, cannot simply consider thermal shock resistance (TSR) of the material its own but need to take the external constraint conditions and the thermal environm...

In this study, HfB2-SiC-graphite composites were fabricated using spark plasma sintering at 1900 ℃ for 10 min. The effect of graphite content on the microstructure and mechanical properties was studied; also, oxidation resistance prepared investigated 1400 32 h. Weight changes thickness formed oxide layer measured. relative density, toughness strength SPSed increased with raising up 2.5 wt% the...

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 ...