Evaluation of Seven Ductile Fracture Criteria for Failure Prediction of AZ31 Sheet in Warm Forming

Seven commonly used ductile fracture criteria are briefly reviewed and the validity of predicting the failure of AZ31 Mg alloy sheet by using these ductile fracture criteria is evaluated. Through fitting the experimental FLCs, the damage parameters for these ductile fracture criteria are determined firstly. Integrating these seven ductile fracture criteria into Abaqus/Explicit via VUMAT subroutine, the warm deep drawing process of AZ31 Mg alloy sheet is simulated. The limit drawing ratios (LDR) of AZ31 Mg alloy sheet at different temperature are predicted. The comparison of predictions with the experimental results has shown that the combination of the finite element simulation and the ductile fracture criterion is useful for predicting the fracture occurred in warm deepdrawing of AZ31 Mg alloy sheet.