Fracture Behavior Simulation of 3D-C/SiC Under Stress and in Oxidation Environment

Oxidation process of unstressed or low stressed 3D-C/SiC was controlled by reaction kinetics under 1000°C and diffusion kinetics above 1000°C respectively. While the oxidation process of high stressed 3D-C/SiC was controlled by reaction kinetics with the whole temperature range from 700°C to 1300°C, because the microcracks can not close up under high stress condition and oxygen can attack carbon fiber and Pyrolytic Carbon in both low temperature and high temperature. Fuzzy logic modeling technique was used to simulate the fracture behavior of test samples under two stress levels(60±20MPa and 90±30MPa), and the temperature range from 700°C to 1300°C. Most of the samples fractured at root part under low stress level; while the samples fractured at middle part under higher stress level. The simulated results accorded with the experiments.