Oxygen Solubility in Titanium-Containing Melts of the Ni–Co System

Abstract

Thermodynamic analysis is performed for the oxygen solutions in titanium-containing melts of the Ni–Co system. The equilibrium constants of the reactions of titanium with oxygen, activity coefficients at infinite dilution, and interaction parameters in melts of various compositions at 1873 K are determined for the first time. The titanium contents at the equilibrium points between the oxide phases TiO₂, Ti₃O₅, and Ti₂O₃ are determined. The dependences of the oxygen solubility on the titanium content in the studied melts are calculated. The deoxidation ability of titanium decreases with an increase in the cobalt content to 40% and then increases as the cobalt content in the melt further increases. The titanium contents at the minimum points on the curves of the oxygen solubility and the corresponding minimum oxygen contents are determined.