Ablation mechanism of C/C-SiC and C/C-SiC-ZrC composites in hypersonic oxygen-enriched environment

In this study, C/C-SiC and C/C-SiC-ZrC composites were prepared via chemical vapor infiltration and polymer infiltration pyrolysis, and the ablation mechanism under hypersonic oxygen-rich environmental conditions was investigated. The C/C-SiC composites demonstrate an excellent ablation resistance in a hypersonic oxygen-rich environment with a relatively low temperature and speed of approximately 1800 K and 1100 m/s, respectively. It is only in the ablation center area with higher temperatures that a certain degree of thermochemical ablation was observed. The mass and linear ablation rates of C/C-SiC composites (0.027 g/s and 0.117 mm/s, respectively) showed a significant increase in a hypersonic oxygen-rich environment with a temperature and velocity of approximately 2050 K and 2000 m/s, respectively. The high-temperature ablation resistance of ZrC-modified C/ C-SiC-ZrC composites improved significantly. However, the ZrC ceramic component had a considerable impact on the ablation resistance of the material. The structural integrity of C/C-20SiC-30ZrC composites was relatively high in hypersonic oxygen-rich environments with a jet temperature and velocity of 2050 K and 2000 m/s, respectively, and mass and linear ablation rates were 0.012 g/s and 0.015 mm/s, respectively. When the ZrC content increased by 40%, the ablation resistance of the composite reduced significantly, whereas the mass and linear ablation rates increased to 0.043 g/s and 0.130 mm/s, respectively.

Automated summary

In this study, C/C-SiC and C/C-SiC-ZrC composites were prepared and their ablation resistance under hypersonic oxygen-rich environmental conditions was investigated. The results showed that C/C-SiC composites exhibited excellent ablation resistance at relatively low temperature and speed, while the high-temperature ablation resistance of ZrC-modified C/C-SiC-ZrC composites significantly improved.