Abstract: Aimed at the development requirement and repeatable use in space shuttle, the tensile tests in the oxidation simulation environment of open atmosphere with room temperature and 800 ℃ are proposed for the 2D C/SiC composite material. The coupling test by room temperature high temperature room temperature cycle process with tension tension fatigue load is done. The regulation of mechanical character in different conditions is obtained. The control factor affecting the integrality of surface coating for C/SiC specimen and the translating point are analyzed. A fine static durative strength character is shown for the material in high temperature environment, but the fatigue character is declined evidently during the process of cycling. Based on the model of residual stiffness, a new modified fatigue life prediction method is given fitted for mechanical thermal oxidation coupling condition, in which the factor of cycling process from normal to high temperature and the dimensional size factor affecting the sample’s oxidation are considered. 

Key words: C/SiC composites, Simulated environment, Fatigue test, Damage evolution, Life prediction