Local Approach to Damage in Elasto-Plastic Metal Matrix Composites

Damage is incorporated along with plastic deformation in this model for the analysis of fiber-reinforced metal matrix composite materials. In the formulation, a micromechanical composite model is used in the sense that the matrix and fiber local con stitutive damage relations are treated separately and then linked to the overall response through a certain homogenization procedure. In this process, two local damage tensors M ^M and M ^F are introduced where M ^M accounts for the damage in the ductile matrix such as nucleation and growth of voids, while the tensor M ^F reflects the damage in the fibers such as fiber fracture. The problems of debonding and delamination can be conveniently represented by either M ^M or M ^F , or a combination of both depending on the extent of complexity that is desired of the final constitutive model.