The oxidation life analysis method for SiC/SiC composite components based on an equivalent diffusion coefficient model

A method for the oxidation life analysis of SiC/SiC composite structures was proposed to predict the oxidation life of ceramic matrix composite (CMC) components. In this paper, multiscale diffusion-oxidation simulation of the CMCs' structure can be carried out by establishing the equivalent diffusion coefficient model, to get the microscopic oxidation morphology parameters at each point. Based on the results, the residual stiffness is calculated with the homogenization method. Then, the residual stiffness is taken as the material parameter of element to calculate the stress distribution after oxidation in the CMC structure. And the residual strength of CMCs was calculated by progressive damage analysis. The oxidation life of CMC component is analyzed by judging the failure condition of each element. Finally, the oxidation life prediction of the CMC adjustment sheet under specific loading environment is realized, which is about 1 200 h. The results show that this method is feasible for the calculation of hot end parts under actual complex loads. image