Effect of particle size on anti-oxidation property of mullite coating prepared by pulse arc discharge deposition

Mullite coatings with different particle sizes were prepared on carbon/carbon (C/C)-SiC composites surface by pulse arc discharge deposition (PADD). Phase compositions and microstructures of the as-prepared mullite coatings were characterized by XRD and SEM. The influence of particle size on the microstructures and oxidation resistance of the as-coated samples were investigated. Results indicate that the dense and homogeneous mullite coating was achieved when the size of mullite powder is about 1 μm, which could effectively protect C/C composites from oxidation at 1773 K in air for 156 h with a mass loss of 1.98%.