MICROMECHANICS CHARACTERIZATION OF UNIDIRECTIONAL COMPOSITES DURING MULTIAXIAL PLASTIC-DEFORMATION

This study examined the micromechanics at the scale of reinforcement in a short fiber/whisker reinforced unidirectional composite undergoing elastic/plastic deformation. The equivalent inclusion method was extended to consider composite systems comprising fiber/whisker of variable aspect ratio. The flow rule of matrix material is incorporated such that the composite deformation involved multiaxial loading can be handled. Theoretical predictions are reported on the effects of variable fiber aspect ratio, loading direction, and hydrostatic stress on the macroscopic behavior of the composite and the stress state at the reinforcement scale.