Electron microscopic study of Ti3Al microstructure after deformation at 1073-1273 K

An electron microscopic analysis of the dislocation structure of the Ti3Al intermetallic after high-temperature deformation is performed. It is found that the microstructure of the samples deformed at T = 1073-1173 K contains mobile a and 2c + a superdislocations. Dislocation configurations including a superstructural intrinsic stacking faults are revealed after deformation at T = 1273 K. A scheme of formation of these configurations by the interaction of a superdislocations in the basal and prism planes is proposed. Glissile dislocations with the Burgers vector [0 0 0 1] in prism planes and superdislocations with the Burgers vectors 1/3<21-bar1-bar3> and 1/3<01-bar13> are observed at T = 1273 K. Possible models of the barrier destruction on 2c + a superdislocations in pyramid planes are discussed considering results of the computer simulation of the superdislocation core structure in Ti3Al.