Work

A thermodynamic theory of coupling between point-defect diffusion and dislocation plasticity

Year: 2025

Type: article

Abstract: This article describes a unified, thermodynamically consistent model for irradiation creep that combines dislocation glide and the stress-induced preferential absorption (SIPA) of point defects at dislocations. Central to the model is the premise that the dynamics of point defects, such as interstitials and vacancies, is controlled by temperature, while the dynamics of extended defects, among which dislocations are of prime relevance, is controlled by an effective temperature that pertains to the configurational degrees of freedom that evolve on a much slower time scale than the kinetic-vibrational degrees of freedom and, as such, fall out of equilibrium with the former. Results for thermal and irradiation creep in copper and aluminum suggest that conventional SIPA mechanisms are inadequate to explain the pronounced dependence of the irradiation creep rates on stress and temperature, necessitating nontrivial corrections to the SIPA dislocation climb rates. These results provide important insights into the stress and temperature dependencies of dislocation climb.

Source: Journal of Applied Physics

DOI: 10.1063/5.0257553

Authors: Charles K. C. Lieou, Brian D. Wirth

Institutions: University of Tennessee at Knoxville, Oak Ridge National Laboratory

Language: English

Topic: Fusion materials and technologies

Subfield: Materials Chemistry

Field: Materials Science

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $3,500

Funder: U.S. Department of Energy