On Calibrating Advanced Damage Models Using Sheet Metal Coupon Tests

With increasing requirements on crashworthiness and weight reduction of car body structures, the use of high strength steels has become widespread in modern cars. In contrast to conventional steels, these higher strength steels often show significantly less ductility. In crash loadings this fact can cause crack formation, which must be predicted in crashworthiness simulations. In crashworthiness simulations, several continuum models are available which consider ductile damage. One widely used model is the Gurson model. In the near past, several modifications of the Gurson model were presented, to cure a well-known weakness of this model: No damage evolution is predicted in states of zero mean stress. Due to these extensions, the micromechanical Gurson model is able to describe damage accumulation in states of shear stress. Another damage model, which is able to describe ductile damage, is the GISSMO model. This work is considering possibilities for calibrating advanced damage models and the requirements to ensure calibration.