The dissociation widths of the <10¯1] and ½<11¯2] super-dislocations were calculated under the assumption that the elastic interaction energies and stacking-fault energies which acted on the partial dislocations were equal. The results showed that the dissociation widths of the screw <10¯1] and ½<11¯2] super-dislocations in the anisotropic condition were smaller than those in the isotropic condition. However, the dissociation widths of the edge <10¯1] and ½<11¯2] super-dislocations in the anisotropic condition were larger than, or equal to, those in the isotropic condition. The equilibrium separations of the superlattice intrinsic stacking faults which were formed by the 2-fold <10¯1] and ½<11¯2] super-dislocation dissociations were almost the same in the elastic isotropy condition, but were different in the elastic anisotropy condition. The stacking-fault energy of superlattice intrinsic stacking faults in a high-Nb TiAl alloy, was estimated to be equal to 45 to 55mJ/m2 on the basis of the <10¯1] super-dislocation dissociation, and to be equal to 62 to 69mJ/m2 on the basis of the ½<11¯2] super-dislocation dissociation, by using isotropic calculations. The value was deduced to be about 80mJ/m2, on the basis of both the <10¯1] and ½<11¯2] super-dislocation dissociations, by using anisotropic calculations.

Effect of Elastic Anisotropy on the Dissociation Widths of Super-Dislocations in TiAl. X.P.Song, G.L.Chen: Materials Letters, 2001, 48[5], 273-80