Statistical Thermodynamics of Strain Hardening in Polycrystalline Solids

TL;DR

This paper revisits the statistical thermodynamics framework for dislocation-driven plasticity, explaining rate-hardening anomalies and grain size effects in polycrystalline solids, emphasizing the importance of physics-based nonequilibrium analysis.

Contribution

It provides a systematic rederivation of the thermodynamic equations of motion and applies them to explain experimental hardening behaviors in polycrystals.

Findings

Explains anomalous rate-hardening behavior in 1988

Relates hardening rate to grain size effects

Highlights the importance of nonequilibrium physics in material strength

Abstract

This paper starts with a systematic rederivation of the statistical thermodynamic equations of motion for dislocation-mediated plasticity proposed in 2010 by Langer, Bouchbinder and Lookman. It then uses that theory to explain the anomalous rate-hardening behavior reported in 1988 by Follansbee and Kocks, and to explore the relation between hardening rate and grain size reported in 1995 by Meyers et al. A central theme is the need for physics-based, nonequilibrium analyses in developing predictive theories of the strength of polycrystalline materials.