Equation of motion for grain boundaries in polycrystals  

作　　者：Luchan Zhang Jian Han David J.Srolovitz Yang Xiang 

机构地区：[1]Department of Mathematics,The Hong Kong University of Science and Technology,Clear Water Bay,Kowloon,Hong Kong SAR,China [2]Department of Materials Science and Engineering,City University of Hong Kong,Kowloon,Hong Kong SAR,China [3]Hong Kong Institute for Advanced Study,City University of Hong Kong,Kowloon,Hong Kong SAR,China

出　　处：《npj Computational Materials》2021年第1期580-587,共8页计算材料学（英文）

基　　金：L.Z.acknowledges support from the Hong Kong Research Grants Council General Research Fund 16301720;J.H.acknowledges support from CityU in the form of a Start-up Grant 7200667 and a Strategic Research Grant 7005466;D.J.S.and Y.X.acknowledge support from the Hong Kong Research Grants Council Collaborative Research Fund C1005-19G;D.J.S.also acknowledges partial support from the US Army Research Office under Grant Number W911NF-19-1-0263.

摘　　要：Grain boundary(GB)dynamics are largely controlled by the formation and motion of disconnections(with step and dislocation characters)along with the GB.The dislocation character gives rise to shear coupling;i.e.the relative tangential motion of two grains meeting at the GB during GB migration.In a polycrystal,the shear coupling is constrained by the presence of other grains and GB junctions,which prevents large-scale sliding of one grain relative to the other.We present continuum equations of motion for GBs that is based upon the underlying disconnection dynamics and accounts for this mechanical constraint in polycrystals.This leads to a reduced-order(zero-shear constrained)model for GB motion that is easily implemented in a computationally efficient framework,appropriate for the large-scale simulation of the evolution of polycrystalline microstructures.We validated the proposed reducedorder model with direct comparisons to full multi-disconnection mode simulations.

关 键 词：GRAIN MOTION DISLOCATION 

分 类 号：O73[理学—晶体学]