Dislocation character and operative slip systems in α-Nb5Si3 tested at 1673 K

Dislocation character and operative slip systems in α-Nb5Si3 were examined by transmission electron microscopy. Two-phase alloys comprised of (Nb) and α-Nb5Si3 were used in this study. Although few dislocations were present in the α-Nb5Si3 phase of a pre-deformed alloy, many developed after 15% of compressive deformation at 1673 K. Two types of the Burgers vectors were identified for α-Nb5Si3: <100] and 1/2 < 111]. The glide planes of dislocations were defined by the cross products between the Burgers vectors and the line vectors of the dislocations, by which the slip systems that operate in α-Nb5Si3 at 1673 K were determined as {011)<111], {100)<010], and {001)<100].