Oxidation resistance and mechanical properties of HfC nanowire-toughened ultra-high temperature ceramic coating for SiC-coated C/C composites

To improve the oxidation resistance of carbon/carbon (C/C) composites, a dense HfC nanowire-toughened ultra-high temperature ceramic multiphase coating was prepared on SiC-coated C/C composites by chemical vapor deposition (CVD) and pack cementation. The microstructure, mechanical and oxidation resistance properties of the coating were investigated. The results show that the HfC nanowires in the coating could suppress the cracking of the coating and then improve the toughness of the coating. The flexural property, thermal shock and isothermal oxidation resistance of the coating were all improved due to the incorporation of HfC nanowires.