Effect of tool modeling accuracy on sheet metal forming simulation

This paper describes the effect of tool modeling accuracy on the accuracy of springback simulation in sheet metal forming. Simulations of a two-dimensional draw-bending process are carried out by using the polyhedral tool model and the model whose surface is smoothed by quadratic parametric surfaces proposed by Nagata [1]. It is found that the tool modeling, especially the normal vector accuracy in the present model, plays an important role in the prediction not only of deformation but also of stress distribution. The simulated results show that the tool model based on the so-called Nagata patch enables a more accurate and efficient simulation.