Abstract
The microscopic deformation of a particulate reinforced metal matrix composite was modeled by a unit cell model with Mises and Gurson yield conditions based on metal plasticity. The numerical predictions were compared and calibrated with the results of monotonic experiments of a cast aluminium alloy discontinuously reinforced with SiC particulates with and without thermal cycling. The responses of monotonic work hardening and the microscopic fracture mechanisms were investigated numerically. The micromechanical considerations of monotonic deformation in the particulate reinforced metal matrix composite were examined. (1) Whether there is a plastic deformation band penetrating a matrix or not, is the controlling factor of the magnitude of a work hardening rate for particulate reinforced composites; with or without thermal cycling. (2) For T7 treated composites, the maximum stress in the particle was larger than that of the interfacial average stress. For the composite with thermal cycling, the maximum particle stress was less than that of the interfacial average stress.
