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 contr ol of the material flow during the forming operation. In numerical met hods these drawbeads can be simulated with an equivalent drawbead. In this paper the implementation of an equivalent drawbead model in a fin ite-element code is described. The input for the equivalent drawbead c onsists of a drawbead restraining force, a plastic thickness strain an d a drawbead lift force, which are obtained from a two-dimensional dra wbead simulation or from an experiment. Two different mathematical des criptions of the implementation of the plastic thickness strain are po inted out. The correlation between the simulation results gained with the different algorithms is presented in this work. (C) 1998 Elsevier Science S.A. All rights reserved.