Forming limit prediction by the Marciniak-Kuczynski model coupled with the evolving non-associated Hill48 plasticity model

This study aims to investigate the numerical prediction of forming limits by the Marciniak-Kuczynski localization criterion coupled with an evolving non-associated plasticity model based on the Hill48 model (enHill48). The evolving plasticity model incorporates both the anisotropic hardening and r-value evolution of the selected steel. The coupling algorithm between the enHill48 model and the Marciniak-Kuczynski localization criterion is developed. To reveal the effects of the evolving plasticity and the flow rule formulation on the forming limit prediction, various versions of the Hill48 model are also coupled with the Marciniak-Kuczynski model and further utilized to compare the predicted results. It is concluded that both the flow potential and yield locus are controlling the final localization of the investigated material under the assumption of the non-associated flow rule.