Carbon fiber reinforced silicon carbide-hafnium carbide (C/SiC-HfC) composite was prepared by precursor infiltration and pyrolysis process. Then, ablation behavior of C/SiC-HfC was evaluated in plasma wind tunnel. It was found that oxide layer formed during ablation significantly influenced the surface temperature. Formation of dense HfO₂-SiO₂ layer under low heat flux led to stable surface temperature. Silica (SiO₂) on the surface was gradually consumed when heat flux increased, resulting in conversion of HfO₂-SiO₂ on the surface to HfO₂. Converted HfO₂ with high catalytic coefficient absorbed more energy, causing gradual increase in the surface temperature. Formed oxide layer was destroyed at high heat flux and high stagnation point pressure. After carbon fiber lost the protection of HfO₂-SiO₂ layer, it burned immediately, leading to surface temperature jump.

中文翻译：

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等离子体风洞中前驱体渗透和热解制备的C / SiC-HfC复合材料的烧蚀

碳纤维增强的碳化硅-碳化ha（C / SiC-HfC）复合材料是通过前体渗透和热解工艺制备的。然后，在等离子风洞中评估了C / SiC-HfC的烧蚀行为。发现在烧蚀期间形成的氧化物层显着影响表面温度。在低热通量下形成致密的HfO ₂ -SiO ₂层导致表面温度稳定。当热通量增加时，表面上的二氧化硅（SiO ₂）逐渐消耗掉，导致表面上的HfO ₂ -SiO ₂转化为HfO ₂。转换后的HfO ₂具有高催化系数的分子吸收了更多的能量，导致表面温度逐渐升高。在高热通量和高驻点压力下破坏了形成的氧化物层。碳纤维失去对HfO ₂ -SiO ₂层的保护后，立即燃烧，导致表面温度跃升。