Abstract: To resolve the technical difficulties of accurately deciding cracks in numerical simulation of warm deep drawing，a ductile fracture criterion of magnesium alloy sheet considering temperature effect is put forward. Based on the unidirectional tensile test and warm forming limit test, the material parameters are calculated by the combination method of experiment with FE simulation. Based on this ductile fracture criterion, the warm forming limit of AZ31 magnesium alloy sheet is forecasted. Finally, experimental verifications of limit drawing ratio are also performed. Research results show that the ductile fracture criterion considering temperature effect is suitable for the numerical simulation of warm deep drawing of magnesium alloy sheet, and the deformation mechanism of warm forming is disclosed. The forecast results show good agreement with the experimental results.

Key words: Ductile fracture criterion, Magnesium alloy sheet, Numerical simulation, Temperature effect, Warm deep drawing