The Effect of Matrix Constitutive Model on Residual Thermal Stresses in MMC

A thermomechanical analysis of advanced composites in a wide temperature range is presented. This analysis is based on the micromechanics method of cells. An incremental formulation of the micromechanics model is developed to facilitate the use of various inelastic constitutive theories. These theories incorporate time-dependent and temperature-dependent features for modeling different types of metal matrices. The constitutive models include the Bodner-Partom unified theory of viscoplasticity, the incremental plasticity model, and a power-law creep model. The effect of the cooling rate, taking into account temperature-dependent matrix properties, on residual thermal stresses is subsequently investigated for a SiC/Ti composite using the different models for the matrix phases. Predictions generated using the micromechanics method are compared with available results of finite-element analysis.