Micromechanics based model of fatigue/oxidation for ceramic matrix composites

A micromechanics based model of the thermomechanical behavior of minicomposites is proposed. It is based on the model of mechanical behavior proposed by Lissart et al. [1]. Multiple cracking of matrix and fiber failures are described using a fracture statistics based model. Thermally induced residual stresses are taken into account. Kinetics of interphase degradation or crack healing induced by oxidation at high temperature were introduced. The model was applied to SiC/SiC minicomposites reinforced by Hi-Nicalon multifilament tows. Predictions were found to be in good agreement with the mechanical behavior at room temperature. Trends in deformations in static fatigue at high temperature in air are anticipated.