Prediction of Fracture Limits of Sheet Metals by Using a Damage Mechanics Criterion

In this article, a simple damage failure criterion for anisotropic materials is proposed based on the continuum damage mechanics, in which the effects of microdefects on the states of stress and strain in materials and on the material properties are considered. The sheet metal forming processes under in-plane biaxial stretching deformation are simulated by using finite element method based on a coupled elasto-plasticity with damage constitutive laws, the fracture limit curves for sheet metals are predicted in terms of the proposed criterion. The results show that the computed curves are in agreement with the experimental results.