Power-Law Creep from Discrete Dislocation Dynamics

Shyam M. Keralavarma, T. Cagin, A. Arsenlis, and A. Amine Benzerga

Phys. Rev. Lett. 109, 265504 – Published 26 December 2012

Abstract

We report two-dimensional discrete dislocation dynamics simulations of combined dislocation glide and climb leading to “power-law” creep in a model aluminum crystal. The approach fully accounts for matter transport due to vacancy diffusion and its coupling with dislocation motion. The existence of quasiequilibrium or jammed states under the applied creep stresses enables observations of diffusion and climb over time scales relevant to power-law creep. The predictions for the creep rates and stress exponents fall within experimental ranges, indicating that the underlying physics is well captured.

Received 4 September 2012

DOI:https://doi.org/10.1103/PhysRevLett.109.265504

Authors & Affiliations

Shyam M. Keralavarma¹, T. Cagin^2,3, A. Arsenlis⁴, and A. Amine Benzerga^1,2,*

¹Department of Aerospace Engineering, Texas A&M University, College Station, Texas 77843, USA
²Materials Science and Engineering Program, Texas A&M University, College Station, Texas 77843, USA
³Department of Chemical Engineering, Texas A&M University, College Station, Texas 77843, USA
⁴Lawrence Livermore National Laboratory, Livermore, California 94551, USA