Thermodynamics of the oxygen solutions in chromium-containing Ni–Co melts

Abstract

A thermodynamic analysis of the oxygen solutions in chromium-containing Ni–Co melts at 1873 K has been performed. The equilibrium constants of reactions between chromium and oxygen, the activity coefficients at infinite dilution, and the interaction parameters for melts differing in composition have been determined. The dependences of the oxygen solubility on the cobalt and chromium contents in the melts are calculated. The deoxidizing capacity of chromium slightly decreases as the cobalt content in the melt increases. The composition dependences of the oxygen solubility in the chromium-containing Ni–Co melts have a minimum, which shifts to a high boron content as the cobalt content in the melts increases. The further increase in the chromium addition leads to an increase in the oxygen content in the melt.