Plane Strain Rigid Plastic Finite Element Formulation for Sheet Metal Forming Processes

A rigid plastic finite element model for analysing two-dimensional plane strain sheet metal forming processes is described. The model is based on the large strain formulation using membrane theory, and the material is assumed to be rigid plastic, work hardening and conforms to Hill's anisotropic yield criterion and associated flow rules. The theoretical development follows the work of Kobayashi and Kim on the axisymmetric modelling of sheet metal forming. An application of the model for plane strain cylindrical punch stretching is presented. The results obtained are compared with those provided through an analytical membrane solution described in this work. The agreement found between both solutions is excellent.