DYNAMIC ANTI-OXIDATION BEHAVIOUR OF MoSi₂/SiC COATING SYSTEM FOR CARBON-CARBON COMPOSITES

In the present work, the dynamic anti-oxidation behavior and damage mechanism of MoSi₂-SiC multilayer ceramic coating for carbon-carbon composites were investigated experimentally at various temperatures of 1100~1500℃ under the test for gas jet washout. Experimental data of dynamic oxidation show that the mass loss of MoSi₂/SiC coated carbon-carbon composites decreases, and the ability of oxidation resistance is enhanced with raising the gas temperature up to 1500℃. The mechanism of dynamic oxidation and the concept of the integrity of the coating layer are explained from the theory of mass transportation and the damage of gas jet washout. In this respect, the dynamic oxidation behaviour differs from the static oxidation. The results show that the MoSi₂/SiC ceramic coating for carbon-carbon composites can provide dynamic oxidation protection to C/C composites at temperatures up to 1500℃ in a gas jet environment.