Single crystals of the intermetallic, Ll_2 ordered alloy Ni_78Al_22 were deformed in compression at RT and at 400℃, a temperature below and within the anomalous regime. Transmission electron microscopic (TEM) images were used to analyse the dislocation structures. At RT edge dipoles are prevailing (as in f.c.c, metals) whereas at 400℃ locked screws, screw dipoles and near screw dislocations bowed out on the cube cross-slip plane (010) are predominant. Their formation is caused by a gradual transition from "normal" octahedral cross-slip to the thermal activated cube cross-slip.
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