Dislocation structure in L1 2 Mn-stabilized Al 3Ti deformed between 77 and 873 K

Abstract

Polycrystalline samples of L1 2 Mn-stabilized Al 3Ti were deformed in compression from low temperature to the temperature of the flow stress plateau. The fine structure of the superdislocations was analyzed under weak-beam conditions with particular attention paid to the operating glide systems at different temperatures. The dissociation mode of the dislocations was also addressed in order to discriminate between antiphase boundary-coupled dislocations and Superlattice Intrinsic Stacking Fault (SISF)-coupled partial dislocations. The existence of a strong Peierls effect on undissociated 〈110〉 dislocations during deformation at 573 K is reported, as well as the observation at low temperature of dislocations with 〈100〉 and 〈112〉 Burgers vectors.