Effect of Pre-strain on Anisotropic Hardening and Springback Behavior of an Ultra Low Carbon Automotive Steel

Modeling non-monotonous and/or non-proportional deformation is challenging partly because of lack of constitutive equations and more so because of unavailability of sufficient experimental data. In the present work, two different experiments involving non-monotonous/non-proportional deformation have been proposed. The model based on combined isotropic-kinematic hardening with permanent softening') was utilized to simulate the deformation behavior under such deformation conditions and it was found that the above model was capable of correctly predicting the deformations for both cases considered here. It was also noticed that the incorporation of permanent softening often observed during reverse loading, is important for accurately predicting the deformation when bending-unbending (or strain reversals) takes place.