Superlattice dislocations with <111> Burgers vectors, introduced into NiAl single crystals by compression along the [001] crystal axis at room temperature, were studied by weak-beam transmission electron microscopy. It was found that slip in the <111> direction occurred in a {112} plane. Dissociation, if any occurred, did not exceed 1.5nm; thus establishing a lower limit, for the antiphase boundary energy on {011} and {112} planes, of approximately 500 and 750mJ/m2, respectively. Double images could arise under weak-beam conditions, due to double diffraction at the core of <111> superlattice dislocations.

Weak-Beam Study of <111> Superlattice Dislocations in NiAl. P.Veyssière, R.Noebe: Philosophical Magazine A, 1992, 65[1], 1-13