Study on the failure behaviour of Advanced High Strength Steel considering stamping history

The stamping history has a significant impact on the structural performance of ultra-high strength steel parts. In this paper the material hardening and fracture characteristics of QP1180-EL ultra-high strength steel were tested through experimental methods, and the GISSMO damage model parameters were calibrated based on experiment results. A full process simulation analysis was conducted on the stamping process of a bumper beam, and the damage accumulated during the stamping forming process was evaluated based on the GISSMO damage model. The structural performance differences of bumper beam in three-point bending load case were compared and studied under three conditions: without stamping history, with stamping history but except for damage, and with stamping history. The results show that considering thickness reduction, strain, and stress during the forming process can improve the accuracy of predicting structural peak forces, and considering damage during stamping process can further improve the accuracy of predicting structural failure behaviour.