Dynamic drag of solute atmosphere on moving edge dislocations - Phase-field simulation

A solute atmosphere forms around a dislocation at temperatures where the diffusion of solute atoms is comparable to or faster than the dislocation motion. The dynamic interactions between diffusive solutes and moving dislocations were studied using a phase-field model which takes into account both the chemical interactions in the solid solution and the elastic interactions among solutes and dislocations. The average velocity of dislocations as a function of solute concentration, solute mobility, dislocation mobility, and applied stresses was investigated. The dragging stress of a solute atmosphere and the solute flow around a moving dislocation are presented and analyzed. Some features of dynamic interactions between a single dislocation and its solute atmosphere are observed. (C) 2004 American Institute of Physics.