通过分析C/SiC在高温(1250、1300和1350℃)空气氧化过程中质量、强度、物相、气孔率、微观形貌演变规律,并同时采用动态热机械分析仪测得内耗的变化趋势,研究了氧化对其内耗行为的影响规律,进而为以内耗表征复合材料的氧化行为奠定基础。为明确C/SiC各组元在氧化与内耗行为对应关系中所发挥的作用,进一步研究了SiC陶瓷在1300℃、空气中的氧化与内耗行为之间的对应关系。结果表明:SiC陶瓷氧化对其内耗行为的影响规律不明显且影响程度较弱;C/SiC在氧化过程中的内耗行为受C相的氧化损伤控制,且作用规律明显,其内耗保持率曲线均出现峰值,其中1250、1300和1350℃的峰值分别为6.65、3.48和1.59。 Through the analysis of mass, strength, phase, porosity and microstructure evolution of C / SiC during air oxidation at high temperature (1250, 1300 and 1350 ℃), and simultaneously the change trend of internal friction measured by dynamic thermomechanical analyzer, The effect of oxidation on the internal friction behavior was studied, which laid the foundation for the internal friction characterization of the oxidation behavior of the composites. In order to clarify the role of C / SiC components in the corresponding relationship between oxidation and internal friction behavior, the corresponding relationship between the oxidation and internal friction behavior of SiC ceramics in air at 1300 ℃ was further studied. The results show that the influence of SiC ceramic oxidation on the internal friction behavior is not obvious and the degree of influence is weak. The internal friction behavior of C / SiC in the oxidation process is controlled by the oxidation damage of C phase, and the law of its action is obvious. Peaks occurred at 1250, 1300 and 1350 ° C with peaks of 6.65, 3.48 and 1.59, respectively.