A new class of plastic flow evolution equations for anisotropic multiplicative elastoplasticity based on the notion of a corrector elastic strain rate

TL;DR

This paper introduces a comprehensive framework for anisotropic elastoplasticity at large strains, compatible with multiplicative decomposition and capable of modeling both metals and soft materials effectively.

Contribution

It proposes a novel class of plastic flow evolution equations based on a corrector elastic strain rate, addressing rate issues and ensuring broad applicability.

Findings

Compatible with various stress-strain pairs

Allows easy integration with backward-Euler rule

Does not restrict plastic spin evolution

Abstract

In this paper we present a new general framework for anisotropic elastoplasticity at large strains. The new framework presents the following characteristics: (1) It is valid for non-moderate large strains, (2) it is valid for both elastic and plastic anisotropy, (3) its description in rate form is parallel to that of the infinitesimal formulation, (4) it is compatible with the multiplicative decomposition, (5) results in a similar framework in any stress-strain work-conjugate pair, (6) it is consistent with the principle of maximum plastic dissipation and (7) does not impose any restriction on the plastic spin, which must be given as an independent constitutive equation. Furthermore, when formulated in terms of logarithmic strains in the intermediate configuration: (8) it may be easily integrated using a classical backward-Euler rule resulting in an additive update. All these properties are obtained simply considering a plastic evolution in terms of a corrector rate of the proper elastic strain. This formulation presents a natural framework for elastoplasticity of both metals and soft materials and solves the so-called rate issue.