A NUMERICAL-ANALYSIS OF THE DAMAGE MECHANISMS IN METAL-MATRIX COMPOSITES UNDER CYCLIC DEFORMATION

A model to assess the damage evolution due to reinforcement fracture w as developed for particulate-reinforced metal-matrix composites subjec ted to cyclic deformation. The composite mechanical response was simul ated by means of the finite element analysis of a unit cell and the st resses on the reinforcements were used to calculate the fraction of br oken reinforcements by assuming that the reinforcement strength follow ed the Weibull statistics. The predictions of the model (the fraction of broken reinforcements and the cyclic stress-strain curve) were comp ared with the experimental observations on a 2618 Al alloy reinforced with 15 vol% SiC particulates.