Modelling of PSM to predict the stress in sheet drawing

Abstract

Abstract The solution of stress and load of metal sheet deep drawing serves as a primary basis for guiding production, verifying strength of molds, and optimizing processes. Based on the differential equations, boundary conditions, and model simplification, the stress distribution functions and load solution equations for the drawing deformation process with a blank holder were established and compared with finite element method (FEM) results under the same conditions. Due to the thickness of the flange in deformation zone remains basically unchanged under the action of blank holder, it is reasonable to simplify the solution of deformation to plane strain problem. The PSM and FEM predict that the radial tensile stress and circumferential compressive stress in the flange zones remain basically consistent trends, and the relative error of most of predicted results is less than 5%. The PSM model is unable to consider the influence of the die fillet bending on the stress state of inner and outer sides, leads to the calculated stress and load slightly higher than that of FEM. The solution of stress and load solution by PSM model is reliable and convenient, and the FEM predicts more detailed and accurate results but need consume much larger calculating time. This research is of great significance for improving the teaching efficient and engineering applications of PSM in sheet deep drawing deformation.