Recent advances of research on application of ductile fracture criteria in sheet metal forming process

This paper overviewed the prediction methods of forming limit in sheet metal forming,which included forming limit stress diagram,the maximum forming thinning ratio,forming limit diagram and ductile fracture criteria(DFC).Then this paper pointed out that DFC could predict the forming limit of metal sheet with low plasticity well and meantime take the change of forming path into account.When adopting FEA to model,DFC could not only apply into incremental approach with a fully coupled elastic and plastic damage model,but to one step inverse approach.To accurately predict forming limit,a criterion to reflect material performance in essence was indispensable besides increasing the FEA model accuracy.