Microstructure and ablation behavior of double anti-oxidation protection for carbon-bonded carbon fiber composites

Abstract To improve the oxidation protective ability of carbon–bonded carbon fiber (CBCF) composites, double anti-oxidation protection for CBCF composites were prepared, i.e., ceramic coating-coated CBCF composites combined with ceramic-modified carbon fiber in CBCF matrix. The ablation behavior of modified CBCF composites was tested under an oxyacetylene flame at 1600 °C for 300 s and 800 s, respectively. The results indicate that the ZrB 2 in matrix and ZrB 2 -based ceramic coating can play double protection for CBCF composites during ablation process. The linear ablation rate of the sample after ablation for 300 s and 800 s were −1.1×10 −4 and 8.38×10 −4  cm s −1 , respectively. The modified CBCF composites presented excellent oxidation resistance for 300 s. With the increase of the oxidation time for 800 s, the ZrB 2 -based ceramic coating experienced catastrophic damage. However, the carbon fiber surface only exhibited some circular pits instead of complete oxidation, implying that the ZrB 2 on the carbon fiber surface improved the anti-oxidation and ablation resistance of CBCF composites.