Thermodynamic theory of crystal plasticity: formulation and application to polycrystal fcc copper

TL;DR

This paper develops a thermodynamic framework for crystal plasticity based on the TDT, extending it to multiple slip systems and validating with finite-element simulations on polycrystal copper.

Contribution

It introduces a thermodynamic formulation of crystal plasticity incorporating multiple slip systems using the TDT, providing a physically rigorous model validated by experiments.

Findings

Good agreement with experimental data on polycrystal copper

Extended TDT to multiple slip systems in crystals

Provides new insights into dislocation interactions

Abstract

We present a thermodynamic description of crystal plasticity. Our formulation is based on the Langer-Bouchbinder-Lookman thermodynamic dislocation theory (TDT), which asserts the fundamental importance of an effective temperature that describes the state of configurational disorder and therefore the dislocation density of the crystalline material. We extend the TDT description from isotropic plasticity to crystal plasticity with many slip systems. Finite-element simulations show favourable comparison with experiments on polycrystal fcc copper under uniaxial compression, tension, and simple shear. The thermodynamic theory of crystal plasticity thus provides a thermodynamically consistent and physically rigorous description of dislocation motion in crystals. We also discuss new insights about the interaction of dislocations belonging to different slip systems.