Experimental and thermodynamic assessment of the Nb-Ni-Y system

Abstract

Phase equilibria in the ternary Nb-Ni-Y system are studied experimentally for the first time using x-ray diffraction, electron probe microanalysis, and differential scanning calorimetry in combination with levitation experiments. No ternary compounds exist, while the solubility of third element in binary solid phases is negligible. A subsolidus isothermal section at 750 °C, fields of primary crystallization, invariant reactions, as well as an extension of the liquid miscibility gap from the Nb-Y binary system are determined. Thermodynamic model description for the Nb-Ni-Y system including the binary Nb-Y subsystem is developed and used for calculations of the projection of liquidus surface, isothermal, and vertical sections. © 2008 ASM International.