Crystal plasticity assisted calibration of finite plasticity model and the application to sheet metal forming

In sheet metal forming, the material Is subjected to finite deformation and complex loading paths. Therefore, knowledge about the material properties like the yield locus and the hardening for several load cases is important to model the material behaviour and to simulate forming processes. Due to the fact that experiments are restricted to certain load cases, crystal plasticity methods are used to investigate the material behaviour for multiple load cases and to determine the shape of the yield surface. Thus, only simple tension tests are required for the calibration of the crystal plasticity model. The resulting material properties and additional experimental data are used In order to calibrate a macroscopic finite plasticity model. The model includes an anisotropic yield surface as well as isotropic and kinematic hardening. With regard to the shape of the yield surface of DC04, a Hill type description of the yield surface Is chosen In a first step. The finite plastic ity model is implemented with an efficient algorithm and thus combines fast performance with accuracy in prediction. Deep drawing of a circular cup Is simulated with the model and the simulation results are compared to the experiments. In this case the approach leads to a good match between simulation and experiment