Abstract
〈1010〉 dislocation loops are formed from edge dipoles during the early stages of prismatic slip in sapphire (α-Al2O3). These loops are predominantly edge in character and dissociate by climb into triplets of concentric loops with b = 1/3〈1010〉. These faulted loops lie on {1120} prismatic planes. As the loops shrink by bulk diffusion, they transform to doubly-dissociated faulted loops and then to single faulted loops. The cation fault produced in all these reactions is identical with that previously reported for the glide dissociation of the 〈1010〉 dislocations. The stacking fault energies inferred from the mean radii and extents of dissociation observed are in agreement with the range of those previously reported.
