A New Ductile Fracture Criterion and Its Application to thePrediction of Forming Limit in Deep Drawing

摘要

In the paper, with considering the influence of equivalent plastic strain on void-damage and taking Lemaitre damageequivalent stress as plastic potential, based on continuous damage mechanics theory, a new criterion for ductilefracture is derived. The two key material constants in the criterion are determined by the combination of tension testswith FE simulation. On the basis of the values of stress and strain calculated from commercial finite element software,the forming limit in cylindrical deep drawing of annealed aluminum alloy LY12(M) is predicted by means of the newductile fracture criterion. Experiments verify that the predicted results are in agreement with the experimental ones.Hence, it is reliable to predict the forming limit in deep drawing by means of the new ductile fracture criterion.