Climb kinetics of dislocation loops in aluminium

Abstract
The annealing kinetics of dislocation loops in quenched aluminium has been studied using transmission electron microscopy techniques. An influence of the vicinity of the foil surface on the rate of climb was confirmed. The apparent activation energy for climb of faulted loops was found to be 1·18 ± 0·02 ev and the pre-exponential factor, (7 ± 3)1013 Å/S. The stacking-fault energy was estimated as 110 ergs/cm2 by comparing shrinkage rates of ⅓⟨111⟩ and ½⟨110⟩ loops. A simple model, taking into account rapid diffusion of vacancies along the dislocation, is suggested to account for the observed maintenance of circular shape during loop shrinkage.