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±2.5N, and the weight loss of the coated C/C samples is only 0.50% after oxidation at 1773K for 12h. 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. •A porous surface structure layer was obtained by oxidation pre-treatment.•An inlaid transition structure was constructed at C/C–coating interface.•Pre-oxidation could enhance the interface bonding strength.•Pre-oxidation could improve the oxidation resistance of the coated samples.