A NONLINEAR MICROMECHANICS-BASED ANALYSIS OF METAL-MATRIX COMPOSITE LAMINATES

This paper presents a formulation that performs a direct assembly of a set of equations that relates ply stresses to the constituent microstresses and microstrains up through to the laminate level for any ply layup. The basic tenet of the non-linear laminate formulation in this analysis is that assumptions of the classical laminated plate (CLP) theory for the strain variation in the laminate still apply. Complete details of this analysis from the micromechanics level to the laminate level are presented, and appropriate results of the stress/strain response predictions for monotonic and cyclic applied loads are compared to their analytical and experimental counterparts from previous studies. The non-linear effects of viscoplasticity and fiber/matrix debonding are included in the present formulation, and their impact on both crossply and quasi-isotropic laminates of metal-matrix composites undergoing thermomechanical fatigue loads are examined.