It was recalled that electron microscopic images, of superlattice dislocations, with g•b > 2 could give rise to multiple image peaks whose positions and separations were not always directly related to dislocation dissociation schemes. This was proved by means of image simulation, and was consistent with the predictions of the kinematic theory of image formation. A study of the separation widths of dissociated superlattice dislocations in the present compound was made with g•b = 4 or 8. The dissociation widths were found to be between 3 and 5nm for antiphase boundaries, and between 0 and 1.5nm for complex stacking faults. The corresponding energies were deduced to be between 250 and 420mJ/m2, and greater than 370mJ/m2.

Use of Weak Bragg Reflections for Analysing Superlattice Dislocations in Ni3(Al,Ti). A.Korner, D.J.H.Cockayne, Y.Q.Sun: Philosophical Magazine A, 1993, 68[5], 993-1001