Two stage deformation modeling for DP 780 steel sheet using crystal plasticity

Proper analysis of non-proportional plastic deformation is important for the successful prediction of failure and springback in sheet metal forming of ultra-high strength steels. In this work, a crystal plasticity finite element was applied to analyze the two-stage deformation behavior of a dual phase (DP 780) steel. It was found to be possible to predict the cross-effect observed during the two-stage deformation fairly accurately using the model. It was further felt that accounting for the path dependency of dislocation evolution would still improve the simulation accuracy.