Use of a Mixed Shell Element for Efficient Modeling of Sheet Metal Forming

A mixed shell element is utilized to model the sheet metal forming process. The shell element is capable of representing both bending and membrane actions of the sheet. To model the interface effect, a generalized contact/friction formulation is derived on the basis of a perturbed Lagrangian variational principle together with a classical Couloumb friction law. Two numerical examples are presented to illustrate the application of the proposed formulation.