Stability and cross-slip of [101] superdislocations in γ-TiAl

The stability of superpartial dislocations and their kink pairs in various slip planes is of great interest since the cross-slip of dislocations in γ-TiAl is profuse at high temperatures. Hence, the fundamental understanding of dislocation stability would promote further understanding of cross-slip behavior and anomalous hardening in this material. First the energy factor and the line tension factor have been calculated using Strohʹs sextic formalism from RT to 1173 K. The {111} cross-slip of 〈101] type superdislocations occurs at relatively moderate temperatures while the {010) type cross-slip was observed at high temperatures. The elastic anisotropy effect in terms of interaction forces between superpartials was examined to understand the temperature dependent cross-slip behavior of the superpartial dislocations. The elastic stability of superpartials was checked on (111) and (010) planes. In addition, the interaction energy between a kink-pair formed on superpartials was calculated on various cross-slip planes.