Dissociation of 13〈1126〉{1121} superdislocations in Ti3Al single crystals deformed at high temperatures

The dissociation of 13〈1126〉{1121} superdislocations was studied with transmission electron microscopy in Ti3Al single crystals deformed at high temperatures where the yield stress increased with increasing temperature, attaining a maximum stress at about 700 °C. Near the peak-stress temperature all the dislocations observed were pairs of unlike 16〈1126〉 superpartials loosely bound by an antiphase boundary ribbon about 300 nm wide on {1121} plane. At much higher temperatures, e.g. 900 °C, 16〈1126〉 superpartials tend to decompose to [0001] and 16〈1120〉 dislocations.