A Partly-Explicit Finite Element Formulation for the Forging Process

This paper presents different finite element formulations for the large deformation modelling of a viscoplastic material. A partly-explicit acceleration-pressure formulation is investigated. As the velocity is supposed to be known, we do not have to deal with the possible non-linear feature of the material. Consequently, there is no need to use any Newton-Raphson iteration. The mixed finite element discretization is based on a simple triangular mini-element P1 + /P1. Analysis concerning the bubble properties and its influences on the equation system have been done in order to simplify the formulation. This new dynamic formulation has been successfully implemented in a viscoplastic version of the code Forge2®. Comparisons with implicit static and implicit dynamic algorithms have been performed. Numerical examples are provided to compare the different formulations. A good agreement is noticed on final results.