The impact of dissolved solute atoms on the motion of dislocations in metals, and hence on their plastic response, was examined theoretically. Two regimes of behavior were distinguished; a low velocity regime, in which the dislocation drags a near equilibrium solute cloud, and a high velocity regime, in which the dislocation was alternately trapped and free running. In both regimes, the over-damped motion of a dislocation in the alloy was exactly as it would be in the pure system but with regime-dependent dislocation mobilities. In the low velocity regime, the forces between dislocations were replaced by forces between dislocation-solute cloud quasi-particles. This work provided analytical estimates for the mobilities in the 2 regimes, as well as expressions for calculating quasi-particle interactions. Finally, a prescription was provided for carrying out dislocation dynamics simulations without explicitly incorporating solute degrees of freedom.

Solute Effects on Dislocation Glide in Metals. J.M.Rickman, R.LeSar, D.J.Srolovitz: Acta Materialia, 2003, 51[5], 1199-210