Effect of the local environment on the mobility of dislocations in refractory bcc metals: concurrent multiscale approach

Using a concurrent multiscale approach we demonstrate that the local environment of transition-metal solutes in refractory bcc metals has a large effect on the mobility and slip paths of dislocation. The results reveal that solid solutes or nanoclusters of different geometries may lead to solid-solution hardening or softening, in agreement with experiment, including spontaneous dislocation glide and activation of new slip planes. The underlying electronic mechanism is the change in the anisotropy of the lattice resistance induced by solutes.