Abstract: Compression tests at room and high temperature and creep tests at high temperature have been performed on B2 Nb15A120V and Nb10A120V alloys. At room temperature, in the as-cast state, both alloys exhibited significant ductility in compression. The Burgers vectors of the dislocations were found to be 1/2(111) slipping on {112}. The dislocations showed good mobility. Dislocation clusters also triggered the formation of pseudotwins, which resulted in serrated yielding. In steady state creep, deformation occurred by a combination of dislocation glide and climb, giving a homogeneous microstructure. The dislocations in Nb10A120V were determined to be 1/2(111) slippingon {110} with some (100) segments. After creep at 1100℃, Nb15A120V showed a two phase structure with a few dislocations in the A15 phase but no dislocations in the A2 phase.

Key words: dislocation, pseudotwin, NbAlV alloy