The implementation of an equivalent drawbead model in a finite-element code for sheet metal forming

Drawbeads are applied in the deep-drawing process to improve the control of the material flow during the forming operation. In numerical methods these drawbeads can be simulated with an equivalent drawbead. In this paper the implementation of an equivalent drawbead model in a finite-element code is described. The input for the equivalent drawbead consists of a drawbead restraining force, a plastic thickness strain and a drawbead lift force, which are obtained from a two-dimensional drawbead simulation or from an experiment. Two different mathematical descriptions of the implementation of the plastic thickness strain are pointed out. The correlation between the simulation results gained with the different algorithms is presented in this work.