Phase field disconnections: A continuum method for disconnection-mediated grain boundary motion

Published in Scripta Materialia, 2020

Grain boundary (GB) migration is a key mechanism underlying such phenomena as recrystallization, solidification, and severe plastic deformation. Mounting evidence suggests that the motion of many grain boundaries is mediated through disconnections. Disconnections have been observed and characterized in experiment and atomistic simulation, but have yet to be motivated mechanistically. This work presents a continuum phase field model in which disconnections arise naturally as the result of GB energy nonconvexity, the minimum dissipation potential model for GB migration, and the prescribed coupling factor. The model is applied to a Σ13 copper symmetric tilt grain boundary, and disconnection-mediated migration is observed.

Recommended citation: Runnels B. and Agrawal V., Phase field disconnections: a continuum method for disconnection-mediated grain boundary motion, Scripta Materialia, 186 (2020), 6-10. https://doi.org/10.1016/j.scriptamat.2020.04.042