Transmission electron microscopy was used to investigate dislocation structures in deformed binary and ternary Zr3Al-based alloys. In a binary alloy deformed at between 293 and 673K, the dislocations in the Zr3Al phase consisted of a/3<112>-type partial dislocations bounding superlattice intrinsic stacking fault on {111} planes. The {111}a/3<11¯2> stacking-fault energy was approximately 2mJ/m2 at 673K. In binary specimens deformed between 873 and 1073K, cube slip predominated. The dislocations consisted mainly of a/2<110> pairs separated by antiphase boundary. For this temperature range, the {100}a/2<011> antiphase boundary energy was between 30 and 45mJ/m2. Alloying with niobium or titanium was found to increase the {111}a/3<11¯2> stacking-fault energy and thus increased the tendency to antiphase boundary-type dissociation.

Dislocation Structures in Zr3Al-Based Alloys. P.Holdway, A.E.Staton-Bevan: Journal of Materials Science, 1986, 21[8], 2843-9