Synergistic effects of temperature, oxidation, loading frequency and stress-rupture on damage evolution of cross-ply ceramic-matrix composites under cyclic fatigue loading at elevated temperatures in oxidizing atmosphere

In this paper, the synergistic effects of temperature, oxidation, loading frequency and stress-rupture on damage evolution of cross-ply ceramic-matrix composites (CMCs) under cyclic fatigue loading at elevated temperatures in oxidizing atmosphere have been investigated. The Budiansky-Hutchinson-Evans shear-lag model was used to describe the micro stress field of the damaged composite considering interface wear and interface oxidation. The damage parameters of fatigue hysteresis dissipated energy, fatigue hysteresis modulus, and fatigue peak strain have been used to monitor the damage evolution inside of CMCs. The relationships between damage parameters and internal damage of matrix cracking, interface debonding and slipping have been established. The experimental fatigue hysteresis, interface slip lengths and peak strain of cross-ply SiC/MAS composite under cyclic fatigue loading at different testing temperatures, loading frequency and stress-rupture time in air condition have been predicted.