Inverse vs Incremental Numerical Approaches for Ductile Damage Prediction in Sheet Metal Forming

Abstract : This paper aims to develop a simplified approach for the numerical prediction of the occurrence of ductile damage in sheet metal forming processes. This approach called "Inverse Approach" (I.A.) uses an integrated elasto-plastic constitutive equations coupled with a simplified isotropic ductile damage model. This efficient and fast approach allows to quickly study the influence of process parameters on the quality of the final product. This I.A. is qualitatively compared to a classical incremental approach based on more realistic constitutive equations fully coupled with damage effects. The numerical results show the efficiency, correlation and errors of the I.A. with respect to the incremental approach. A better agreement should be obtained by using our newly developed Pseudo-Inverse Approach considering the loading history.