A finite-element analysis of sheet metal forming processes

A computational method based on the membrane theory for the analysis of axisymmetric sheet metal forming processes such as punch stretching, deep drawing and hydroforming is presented. The elastic-plastic finite element approach is based on the flow rule associated with Hill's quadratic yield criterion for anisotropic material. The total Lagrangian formulation and virtual work theory are used to derive the stiffness equations and the relationship between displacement and strain. Some examples on the stretching, drawing and hydroforming of metal sheets are considered, and the computed results are compared with experimental data and with the results from existing numerical solutions.