The core structures and mobilities of kinks on ½<110> screw dislocations in the L10 structure were simulated by using embedded-atom method potentials which were fitted to the bulk properties of γ-TiAl. Two types of kink were simulated. These were a half-height kink, in which the kink height was ¼<1¯12>, and a full-height kink in which the kink height was ½<1¯12>. Both kinks were diffuse, and spread out over a distance of 1.3nm in the case of the half-height kink and over 2.8nm in the case of the full-height kink. Both were found to move under a stress of less than 0.0005 times the shear modulus in the glide plane. This value was about an order of magnitude lower than the simulated friction stress of an unkinked screw dislocation. On the basis of available experimental data, on the low-temperature deformation of γ-TiAl, it was suggested that kinks significantly modified the friction stress of dislocations in this phase.

Simulation of Dislocation Single Kinks in γ-TiAl using Embedded-Atom Method Potentials J.P.Simmons, S.I.Rao, D.M.Dimiduk: Philosophical Magazine Letters, 1998, 77[6], 327-36