Theory of kink migration in dilute BCC alloys

Plastic deformation in elemental BCC metals and dilute alloys is controlled by the slower of kink pair nucleation migration processes along screw dislocations. In facilitated inhibited, leading to a concentration- temperature-dependent transition from dominance dominance. Here, an analytical statistical model for stress-dependent barrier developed validated. The depends only on clearly-defined solute/screw dislocation interaction parameter, width, length between jogs. analytic extensively validated via fully atomistic nudged-elastic band calculations stochastic simulations Fe-Si alloy. Combined with recent double-kink theory, fully-analytic temperature- concentration-dependent flow stress obtained that includes control. overall applied W-Re using independently-determined material properties good agreement experiments over range concentrations temperatures. Overall, two theories represent unified, fully-statistical, parameter-free understanding strength alloys.