Adaptive finite element remeshing in a large deformation analysis of metalpowder forming

In this paper, a general framework for the finite element simulation of pow der forming processes is presented. A large displacement formulation, based on a total and updated Lagrangian formulation and an adaptive finite eleme nt strategy based on error estimates and automatic remeshing techniques are utilized. To describe the constitutive model of the highly non-linear beha viour of powder materials, an elliptical cap model based on a hardening rul e to define the dependence of the yield surface on the degree of plastic st raining is applied. The interfacial behaviour between the die and powder is modelled by using a plasticity theory of friction in the context of an int erface element formulation. Finally, the powder behaviour during the compac tion of a set of complex shapes are analysed numerically. The simulation of the deformation is shown as well as the distribution of relative density c ontours at different time stages. The results clearly indicate that the alg orithm makes it possible to simulate the powder forming problems efficientl y and automatically. Copyright (C) 1999 John Wiley & Sons, Ltd.