Micromechanical Evolutionary Elastoplastic Damage Model for Fiber-Reinforced Metal Matrix Composites With Fiber Debonding

A micromechanical evolutionary damage model is proposed to predict the overall elastoplastic behavior and interfacial damage evolution of fiber-reinforced metal matrix composites. Progressive debonded fibers are replaced by equivalent voids. The effective elastic moduli of three-phase composites, composed of a ductile matrix, randomly located yet unidirectionally aligned circular fibers, and voids, are derived by using a rigorous micromechanical formulation. In order to characterize the overall elastoplastic behavior, an effective yield criterion is derived based on the ensemble-area averaging process and the first-order effects of eigenstrains.