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以低密度C/C为坯体,采用前驱体浸渍裂解法(PIP)制备ZrC-SiC-C/C复合材料,研究其微观结构和烧蚀性能,并探讨其抗氧化烧蚀行为。结果表明:ZrC-SiC双元陶瓷相弥散分布于基体中,且各相界面结合良好;ZrC-SiC-C/C复合材料表现出良好的抗氧化烧蚀性能,经2 200℃/120s等离子体烧蚀后,其线烧蚀率和质量烧蚀率分别为1.67×10~(-4) mm·s~(-1)和6.04×10~(-4) g·s~(-1)。烧蚀温度为2 200℃时,材料表面形成的ZrO_2-SiO_2二元共熔体系氧化膜,有效抑制氧化性气氛向材料内部的渗透,减缓火焰对材料的剥蚀作用;烧蚀温度为2 500℃时,材料表面形成以表层为ZrO_2和底层为ZrO_2-SiO_2二元共熔体系的氧化膜,其中ZrO_2层阻挡热量向内部传递,有助于底层形成致密的氧化层。
ZrC-SiC-C / C composites were prepared by precursor impregnation and pyrolysis (PIP) using low-density C / C as the green body. The microstructure and ablation properties of the composites were investigated. The results show that the ZrC-SiC binary ceramic phase is dispersed in the matrix and the interface of each phase is well bonded. The ZrC-SiC-C / C composites show good anti-oxidation ablation performance. After 2 200 ℃ / 120s plasma After ablation, the ablation rate and mass ablation rate are 1.67 × 10 -4 mm · s -1 and 6.04 × 10 -4 g · s -1, respectively. When the ablation temperature is 2 200 ℃, the oxide film of ZrO_2-SiO_2 binary eutectic formed on the surface of the material can effectively inhibit the infiltration of the oxidizing atmosphere into the material and reduce the ablation effect of the flame on the material. The ablation temperature is 2 500 ℃ , The oxide film is formed on the surface of the material with the ZrO 2 as the surface layer and the ZrO 2 -SiO 2 as the eutectic layer. The ZrO 2 layer blocks the heat transfer to the inside and helps to form a dense oxide layer at the bottom.