Finite element analysis of sheet metal forming with reconfigurable tooling

Nonlinear finite element simulation is employed in this work to investigate some of the unique aspects of forming sheet metal parts with reconfigurable tooling. The ability to change the shape of the die also introduces compliance into the behavior of the reconfigurable tool. This compliance, which depends on the thickness and material properties of the polymer material used in the forming operation, minimizes the development of local deformations called dimples. However, it also affects the overall geometry of the part. In this paper, these concepts are explained and the local and global response of several sheet metal parts are demonstrated with results from nonlinear finite element simulations of sheet metal forming operations with reconfigurable tooling. Explicit time integration has been used for the simulation of the forming of the parts and implicit, static finite element analysis for the springback step. The finite element simulations have also been validated with measurements from laboratory experiments.