Modeling of the ductile damage: Application for bar shearing

The finite element method is becoming a reliable tool for designing manufacturing processes. Even in bar shearing, which is a basic operation in the metalworking industry, the finite element method is increasingly employed for the optimization of the process. Ductile damage modeling is crucial thereby. Recent experimental investigations have shown that, in particular, triaxiality and temperature must be considered in the constitutive description of damage in the shear zone. In this context, the Hooputra's criterion is in this work applied for the numerical simulation of shearing taking account of different stress states and temperatures. The parameterization of the model is based on wide experimental investigations. Characterization tests on smooth and notched cylindrical specimens as well as on flat shear specimens are carried out. The selected material for this investigation is the aluminum alloy AW6082. Subsequently, the numerical calculation of shearing is performed. By comparing the simulation results with data from experimental shearing, the importance of the consideration of the temperature gradients and the different triaxiality values in the shear zone is proven.