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.

X.Shi, G.Saada, P.Veyssière: Philosophical Magazine Letters, 1995, 71[1], 1-9