Characterization and modelling of the damage behavior of extruded aluminum profiles for crash simulations

The damage behavior of aluminum profiles depends strongly on the stress state. Many investigations have shown that both ductile and shear fracture have to be taken into account in damage analysis. Since fracture strains of aluminum profiles are relatively low, damage modelling has to be included in component simulations. However, it is an open question, which kind of damage model can be used for crash simulations and which tests should be performed in order to calibrate the model. An extruded aluminum profile with double chambers of AA6060-T79 was characterized under different stress triaxialities and shear ratios. The damage criteria IDS (Instability, Ductile and Shear fracture) in ABAQUS/Explicit were used for the simulations. An explicit relationship between triaxiality and shear ratio was derived for plane stress state. The influence of the model parameter ks on the overlapping of both criteria (ductile and shear fracture) was systematically studied for shell element applications. The applied damage model was validated by comparing experimental and calculated results of component tests.