Constitutive modelling of path-dependent plastic behaviour at large strains

摘要

Anisotropic hardening is a dominant feature of the plastic response of metals to cumulative strain. Yet good experimental data in adequate quantity is lacking at the present time. Theoreticians seeking to model plastic behaviour realistically have long been handicapped by this scarcity. Sporadic suggestions for augmenting the classical constitutive framework are over-simplistic in principle and too restricting in practice. All ignore the complex path-dependence of yield surface geometry. In that regard an interim course of action is proposed, pending more data: it is compatible with the classical framework and offers unlimited flexibility. Its practical application is illustrated by a theoretical analysis of some aspects of present-day experimentation at large strains.