Design of large-deformation steady elastoplastic manufacturing processes. Part I: a displacement-based reference frame formulation

A reference frame formulation for the analysis of large-deformation steady- state processes is proposed. The displacement and material state variables appear as the primary response fields in this mixed formulation. Unlike dis placement-based Lagrangian formulations, our formulation does not require a transient analysis to simulate a quasi-steady process and yields results t hat are free of numerical oscillations and which require considerably less computational effort. And unlike velocity,based Eulerian methods, our formu lation does not require free surface corrections or streamline integration algorithms. A novel contact algorithm based on the mapping structure of the reference frame kinematic descriptions is developed. The formulation is us ed to analyse drawing and rolling processes. The results obtained from our analysis are in agreement with those obtained from a computationally intens ive transient Lagrangian analysis. Copyright (C) 2000 John Wiley & Sons, Lt d.