Matrix cracking and debonding of ceramic-matrix composites

The effects of matrix cracking and debonding which occur in ceramic-matrix composites are described by a micromechanical model. The cracking and debonding processes induce loss of stiffness, inelastic strains, hysteresis loops and crack closure. These features are analysed within the framework of Continuum Mechanics by the introduction of internal variables identified in the micromechanical analysis. The evolution laws of the internal variables can be determined by combining the experimental data with micromechanical modeling. The influences of residual stress fields due to processing are also included. Comparisons are made between theoretical predictions and the results of experiments performed on layered materials.