Based on recent advances in phase-field models for integrating phase and defect microstructures as well as dislocation dynamics, the interactions between diffusional solutes and moving dislocations under applied stresses were studied in 3 dimensions. A new functional form for describing the eigenstrains of dislocations was proposed, eliminating the dependence of the magnitude of the dislocation Burgers vector on the applied stress and providing correct stress fields of dislocations. A relationship between the velocity of the dislocation and the applied stress was obtained by theoretical analysis and numerical simulations. The operation of Frank–Read sources in the presence of diffusional solutes, the effect of chemical interactions in solid solution on the equilibrium distribution of Cottrell atmosphere, and the drag effect of Cottrell atmosphere on dislocation motion were examined. The results demonstrated that the phase-field model correctly describes the long-range elastic interactions and short-range chemical interactions that control dislocation motion.

Effect of Solutes on Dislocation Motion - a Phase-Field Simulation. S.Y.Hu, Y.L.Li, Y.X.Zheng, L.Q.Chen: International Journal of Plasticity, 2004, 20[3], 403-25