Phase Equilibria of the Sn-Ni-V System at 800°C

Ternary Sn-Ni-V alloys were prepared and annealed at 800°C for 60 days. The annealed alloys were metallographically examined, and the equilibrium phases formed were identified on the basis of compositional determinations and x-ray diffraction analysis. The isothermal section of the ternary Sn-Ni-V system at 800°C was proposed. Two ternary compounds, VNi2Sn and V2NiSn, were found in the system. V2NiSn is nearly a stoichiometry compound, while VNi2Sn has a wide composition range at 800°C. It spans 24.6 at.% to 49.6 at.% V, 50.6 at.% to 31.2 at.% Ni, and 19.2 at.% to 24.8 at.% Sn. VNi2Sn (30V-45Ni-25Sn) has a congruent melting temperature of 1095.6°C. Moreover, the maximum solubility of V in Ni3Sn2 can reach 10.3 at.%, and that in Ni3Sn is 1.9 at.%. Up to 4.2 at.% Ni dissolves in V3Sn.