Ablation resistance of SiC–ZrC coating prepared by a simple two-step method on carbon fiber reinforced composites

• A simple two-step production method for anti-ablation coating is proposed.
• A mosaic and dense coating structure is achieved by the two-step method.
• The coating can protect C/C composites under high-temperature gas flow.
• The protection mechanism of coating reveals the reasons of coating failure.

SiC–ZrC ablation resistance coating was prepared on the surface of carbon fiber reinforced carbon (C/C) composites by simple pack cementation combined with low-cost slurry infiltration method. The results showed that SiC–ZrC coating could effectively protect C/C composites from ablation for 45 s at 3723 K under oxyacetylene torch. The mass and linear ablation rates (0.038 ± 0.01 mg/(s cm2) and 2.42 ± 0.15 μm/s) were largely reduced compared with that of uncoated C/C composites (0.530 ± 0.01 mg/(s cm2) and 1.75 ± 0.15 μm/s) after ablation for 20 s. The good ablation protective ability of SiC–ZrC coating is mainly attributed to the volatilization of SiO2 and the formation of ZrO2.