The crucial role of chemistry on mobile properties of dislocation

Dislocation-solute interactions are ubiquitous in solids, yet their dual nature in strengthening or softening the material is not well understood. Results of a novel concurrent multiscale approach reveal that the local environment of W solutes in Ta has a dramatic effect both on the dislocation mobility and slip paths. W solutes can enhance or reduce the mobility, and may result in spontaneous dislocation glide. The atomistic mechanism responsible for the dual nature of solutes is elucidated.