Finite-temperature screw dislocation core structures and dynamics in α-titanium  

作　　者：Anwen Liu Tongqi Wen Jian Han David J.Srolovitz 

机构地区：[1]Department of Materials Science and Engineering,City University of Hong Kong,Hong Kong SAR,China [2]Department of Mechanical Engineering,The University of Hong Kong,Hong Kong SAR,China

出　　处：《npj Computational Materials》2023年第1期12-24,共13页计算材料学（英文）

摘　　要：A multiscale approach based on molecular dynamics(MD)and kinetic Monte Carlo(kMC)methods is developed to simulate the dynamics of an(a)screw dislocation inα-Ti.The free energy barriers for the core dissociation transitions and Peierls barriers for dislocation glide as a function of temperature are extracted from the MD simulations(based on machine learning interatomic potentials and optimization);these form the input to kMC simulations.Dislocation random walk trajectories from kMC agree well with those predicted by MD.On some planes,dislocations move via a locking-unlocking mechanism.Surprisingly,some dislocations glide in directions that are not parallel with the core dissociation direction.The MD/kMC multiscale method proposed is applicable to dislocation motion in simple and complex materials(not only screw dislocations in Ti)as a function of temperature and stress state.

关 键 词：DISLOCATION DYNAMICS LOCKING 

分 类 号：TP39[自动化与计算机技术—计算机应用技术]