Abstract The gradient HfB2 modified SiC coating was prepared on the surface of SiC-coated C/C composites by in-situ synthesis. Anti-oxidation behaviors of the coated C/C samples at 1773, 1873 and 1973 K were investigated. The results show that the gradient HfB2 modified SiC coatings possess excellent oxidation resistance, which can protect C/C substrates from oxidation for 800, 305 and 100 h at 1773, 1873 and 1973 K, respectively. In addition, with the oxidation temperature increasing, the evaporation of the Hf-Si-O glass layer and the active oxidation of SiC were accelerated, which is the reason for the worst oxidation resistance of the sample at 1973 K among the three temperatures.

中文翻译：

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C/C复合材料梯度HfB2-SiC多层抗氧化涂层

摘要 采用原位合成法在SiC 包覆的C/C 复合材料表面制备了梯度HfB2 改性SiC 涂层。研究了涂层 C/C 样品在 1773、1873 和 1973 K 下的抗氧化行为。结果表明，梯度 HfB2 改性 SiC 涂层具有优异的抗氧化性，可分别在 1773、1873 和 1973 K 下保护 C/C 基体免受氧化 800、305 和 100 h。此外，随着氧化温度的升高，Hf-Si-O玻璃层的蒸发和SiC的活性氧化加速，这也是样品在1973 K的三个温度中抗氧化性最差的原因。