Dephosphorization of complexly alloyed nickel melts under vacuum induction melting conditions: I. Thermodynamics of dephosphorization

A thermodynamic computer simulation of the oxidation potential of a gas-melt-ceramic (80 wt% MgO, 20 wt % Al₂O₃) system under vacuum induction furnace conditions is used to find that the major contribution to this potential at temperatures ranging from 1673 to 2273 K is made by a nickel melt with additives of nickel protoxide. This provides the possibility of oxidative dephosphorization of the metallic melt. The computation of the saturated vapor pressure of phosphorus compounds with the IIA group elements shows that the data obtained for magnesium, calcium, and barium metaphosphates and europium orthophosphate at 1873 K indicate the principal possibility of melt dephosphorization by the evaporation of these compounds under oxidative conditions.