Interaction of vanadium with iron and antimony at 870 and 1070 K

The isothermal sections of the phase diagram of the V-Fe-Sb ternary system have been constructed at 870 and 1070 K by means of X-ray and electron-probe microanalyzer (EPMA) analyses over the whole concentration range. The existence of the one ternary phase, VFeSb, with MgAgAs- and Ni₂In-type structures was observed at 870 and 1070 K, respectively. The solid solution formed based on the binary Fe_2-xSb (Ni₂In-type) compound reaches up to 12 at.-% of V at 870 K and 40 at.-% at 1070 K, respectively. Differential scanning calorimetry (DSC) analysis, magnetic susceptibility measurements, and electronic structure calculations showed the absence of a VFeSb polymorph phase transition and indicate that the hexagonal phase is part of the V_yFe_2-xSb solid solution.