Martensitic Transformations of the Titanium–Nickelide Alloys with Different Alloying Additions

Martensitic transformations of the TN-10 titanium-nickelide alloys doped with V, Nb, and Ag at a level of 1 at % are studied. It is shown that the alloying elements (Ag, Nb, and V) cause an increase in the elastic stress inside the B 2-phase structure and the consequent increase in the start temperature of the direct martensite transformation. Vanadium significantly affects such a temperature and provides an increase by about 45°C. Complicated martensite transformations ( B 2 → R → B 19') take place in alloys with vanadium and silver, and simple transformations ( B 2 → B 19') occur in alloys with niobium.