Improved oxidation protective ability of SHS powder-synthesized ZrB₂-MoSi₂-SiC-Si coating on carbon/carbon composites

ZrB₂-MoSi₂-SiC-Si coatings were prepared by gaseous silicon infiltration on the carbon/carbon composites, and the powders synthesized by the self-propagating high-temperature synthesis method (SHS) were used as the raw materials to benefit the oxidation protective ability of the coatings. The ZrB₂-MoSi₂-SiC-Si coatings prepared from commercial powders (CP coated samples) were used as a comparison. After sintering, the structure of the coating prepared with SHS powders is denser than the CP coated sample with a density of 3.5 g/cm³. After 62 h of oxidation tests at 1500 °C, the mass loss of the SHS coated sample was only 0.28 %, which was 32 % lower than that of the CP coated sample. The ability of SHS coatings to exhibit better oxidation protection is attributed to the higher oxidation stability and sintering activity of the SHS powders than that of commercial ones.