Coupled elastic–plastic damage model for a porous aggregate with an incompressible matrix displaying tension–compression asymmetry

A significant strength differential effect (different behavior in tension versus compression) is observed at the polycrystal level, if either twinning or non-Schmid type slip are contributors to plastic deformation at the single crystal level. Despite recent progress in modeling the asymmetry in yielding, a description of damage by void growth in such materials remains a challenge. In this paper, an elastic–plastic damage model with yielding described by a plastic potential that depends on all invariants of the stress deviator is used. Single-element tests illustrate the salient features of the model. Simulation results of sheet-metal blanking show that if the compressive strength of the matrix is lower than its tensile strength, void growth and damage expansion is restricted.