Abstract C/SiC composites had been prepared by PIP process. The evolution of microstructure and mechanical properties after high-temperature (>1500 °C) oxidation were discussed and compared. The results showed that PIP-C/SiC composites had been severely damaged after oxidation tests, micro-cracks and holes emerged along with the increasing of the oxidation temperature, which lead to the decreasing of mechanical properties. After high-temperature flexural tests, the thermal mismatch between C fibers and SiC matrix gradually caused the expansion of micro-cracks, which lead to the decreasing of flexural strength. The mechanical performance deteriorated because defects in the matrix increased and some fibers were oxidized. For long-time use at higher temperature (≥1600 °C), it was necessary to develop a more protective coating with higher stability and melting temperature.

中文翻译：

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高温氧化后PIP-C/SiC复合材料的微观结构和力学性能演变

摘要 C/SiC 复合材料采用PIP 工艺制备。讨论和比较了高温（> 1500°C）氧化后微观结构和机械性能的演变。结果表明，PIP-C/SiC复合材料在氧化试验后受到严重破坏，随着氧化温度的升高出现微裂纹和孔洞，导致力学性能下降。高温弯曲试验后，C纤维与SiC基体之间的热失配逐渐引起微裂纹扩展，导致弯曲强度下降。由于基体中的缺陷增加和一些纤维被氧化，机械性能变差。在较高温度（≥1600°C）下长期使用，