Nanowire-toughened transition layer to improve the oxidation resistance of SiC–MoSi2–ZrB2 coating for C/C composites

• A SiC nanowire-toughened inlaid transition layer was obtained by a combined method of pre-oxidation treatment and chemical vapor deposition.
• Oxidation resistance of the coated samples was improved by the as-obtained transition layer.
• The transition layer with an inlaid structure and the pinning of the nanowires could alleviate the mismatch of thermal expansion coefficient between C/C substrate and SiC–MoSi2–ZrB2 coating.

To enhance the oxidation resistance of SiC–MoSi2–ZrB2 coating for C/C composites, pre-oxidation treatment and chemical vapor deposition were applied to construct a SiC nanowire-toughened inlaid transition layer between C/C and SiC–MoSi2–ZrB2 coating. The results show that the coating prepared with pre-oxidation and SiC nanowires has better oxidation resistance, which can protect C/C for 124 h at 1773 K in air with the weight loss per unit area of 1.1 mg cm−2. The synergistic effect of the inlaid structure of the transition layer and SiC nanowires plays positive role on alleviating the mismatch of thermal expansion coefficient between C/C and SiC–MoSi2–ZrB2 coating.