Influence of constitutive equations on the accuracy of prediction in sheet metal forming simulation

Paper in proceeding, 2008

During the last three decades, numerical simulation has gradually extended its applicability in the field of sheet metal forming. Constitutive modelling is one of the domains closely related to the development of numerical simulation tools. The paper is focused on the development of new phenomenological yield criteria developed in the CERTETA research centre able to describe the anisotropic response of sheet metals. The numerical tests presented in the paper prove the capability of the equivalent stresses to model the inelastic response of a large variety of materials (steel and aluminium alloys). The last section of the paper is devoted to a comprehensive testing of the new yield criterion as implemented in the finite-element code AUTOFORM 4.1. With this aim in view, the authors have chosen the bulging and cross deep drawing benchmarks. The test proves the capability of the yield criterion to describe the effects of the plastic anisotropy of the sheet metals subjected to industrial forming processes.