Phase Composition, Microstructure, Multiple Shape Memory Effect of TiNi_50-xV_x (x = 1; 2; 4 at.%) System Alloys

The phase composition, microstructure, and multiple shape memory effect of TiNi_50-xV_x alloys were studied in this work. The phase composition of the TiNi_50-xV_x system is the TiNi matrix, spherical particles of TiNiV, the secondary phase Ti₂Ni(V). Doping of TiNi alloys with vanadium atoms leads to an increase in the stability of high-temperature B2 and rhombohedral R-phases. An increase in the atomic volume with an increase in the concentration of the alloying element V from 1 to 4 at.% was established. Vanadium doping of the Ti-Ni-V system alloys leads to an increase in the temperature interval for the manifestation of the multiple shape memory effect. It has been established that the value of the reversible deformation of the multiple shape memory effect both during heating and during cooling increases linearly from 2 to 4% with an increase in the vanadium concentration.