Finite element simulation of sheet metal stamping with polycrystalline plasticity

Abstract

The rate-dependent crystalline plasticity constitutive model is introduced into Mindlin shell element and dynamic explicit finite element method. A tangent modulus method is employed to calculate plastic strain increment. The crystal orientations are as- signed to finite element integration points and the stress of polycrystalline is calculated according to the normal distribution charac- teristic of orientation distribution function (ODF) in orientation space. A program is developed based on the proposed crystalline plasticity dynamic explicit finite element model to simulate sheet metal stamping as well as predict texture evolution. The stamping process of a rolled aluminum sheet, whose initial main textures are Cu and S texture for a square punch is numerically studied. The validity of proposed model is proved through the comparison between numerical results and experimental ones. By the crystalline plasticity finite element method, not only the sheet metal deformation process during stamping can be simulated, but also the evolu- tion of sheet metal texture can be predicted. During the box stamping process, Cu and S textures are not stable and transform to other orientations gradually.