Improvement of the bonding strength and the oxidation resistance of SiC coating on C/C composites by pre-oxidation treatment

To improve the bonding strength and the oxidation resistance of SiC coating by chemical vapor deposition (CVD) for carbon/carbon (C/C) composites, C/C composites were modified by pre-oxidation treatment. It is found that an inlaid transition structure was obtained at the interface between SiC coating and pre-oxidized C/C composites. After pre-oxidation treatment, the interface adhesion strength increases from 23.5 ± 3.2 to 37 ± 2.5 N, and the weight loss of the coated C/C samples is only 0.50% after oxidation at 1773 K for 12 h. The obvious improvement of the bonding strength and the oxidation resistance was mainly attributed to the pre-oxidation of the C/C substrate, forming an inlaid transition layer at the C/C-SiC interface during CVD process.