Atomistic examination of the unit processes and vacancy-dislocation interaction in dislocation climb

Atomistic analyses of thermodynamic and kinetic barriers to the unit processes of dislocation climb in body-centered cubic iron are presented. Binding of vacancies to the core is demonstrated to be equivalent to particle adsorption, thereby reducing the number of independent barriers to unit climb. The extent to which vacancy energetics are poorly predicted by elasticity theory of dislocation strain fields near the core, as well as the deviation of migration barriers near versus far from the core, are also quantified.