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

Abstract

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. (C) 2011 Elsevier Ltd. All rights reserved.