We discuss the possibilities of stabilizing (111) slip in NiAl based on recent results of the atomistic structure of dislocation cores in this material. In previous work it was found that the (111) complete dislocation is stable with respect to partials of 1/2 (111) Burgers vector. However, split configurations were found with a very similar energy. In particular, split configurations that are nearly planar were found, indicating that if this type of dislocation could be stabilized they would possibly result in ductile alloys.
We discuss the possible effects of local disorder and deviations from stoichiometry on core structure concentrating on the objective of stabilizing (111)slip. Atomistic simulations performed to study these effects show that local compositional changes and disorder may have significant effects on the core structure. These effects are most important in the regions of the core where the point defects are localized and it is unlikely that such local changes could be used to successfully stabilize (111) slip. Furthermore, it is not clear whether local changes in ordering and compositional states can follow the dislocation as it moves during the deformation process. We therefore propose that the alloying efforts should be directed towards changing the APB energy of the NiAl-base alloy to a lower value.