Transmission electron microscopic evidence was presented for the annihilation mechanisms which operated during room-temperature plastic deformation of this material. In the case of load orientations which favored the operation of a single-slip system, the short dipoles that were present in foils taken parallel to the slip plane were identified as being elongated closed super-dislocation loops, instead of dipoles which terminated at free surfaces. The fact that dipoles were often aligned in rows, such that one extremity of a given dipole corresponded to the closest extremity of the next dipole in the screw orientation, was explained in terms of the cross-slip properties of Ni3Al-based alloys. The presence of 2 distinct categories of dipole rows was interpreted in terms of 2 different approach mechanisms. The formation of antiphase boundary tubes via the direct annihilation of screw segments was questioned.

The Annihilation of Superdislocations in Ni3Al during Deformation at Room Temperature. Shi, X., Saada, G., Veyssière, P.: Philosophical Magazine Letters, 1995, 71[1], 1-9