The constitutive models in numerical simulation of steady-state metal forming processes

Abstract

The theory of plasticity is in poor condition relative to linear elasticity. All existing formulations are approximate at best, and few have any connection to the fundamental (micromechanical) material mechanism responsible. For this reason, all plasticity theories must be considered empirical. Even worse, detailed testing of a plasticity theory requires extensive, careful experimentation using special machinery and precise interpretation. Accuracy of this data has a big influence on numerical calculation of metal forming processes. The very important problem in numerical simulations is defining the rigid and plastic zones in deformed material. The methods for determining these zones and the basic constitutive models used in numerical simulation of steady-state metal forming processes are analysed in this paper.