Microstructures and deformation behaviour in Nb/10–25at.% Al/20–40at.%V alloys

The phase stability, mechanical properties and deformation mechanisms of a range of Nb/10–25at.% Al/20–40at.% V alloys have been determined over a wide temperature range. These alloys contain a previously unreported stable B2 phase and the volume fraction is directly proportional to the Al/V ratio for these compositions. The B2 phase is inherently ductile even at room temperature and deforms by a combination of martensitic pseudo-twinning and planar slip of paired superpartial dislocations withb =1/2 111 on 110 and 112 . The effect of alloy composition on the phase stability and deformation mechanisms is discussed.