2013 Volume 53 Issue 7 Pages 1161-1164
Thermodynamic information on the equilibrium between dissolved Cr and O in steel melt is the basic knowledge to control Cr content in the stainless steel production process. In the case of using alumina refractories, molten Fe–Cr alloy equilibrates locally with ‘FeO•(Cr, Al)2O3’ solid solution at the interface between the melt and refractories when Cr content in the alloy is low. Wide composition range of ‘FeO•(Cr, Al)2O3’ solid solution is known, and the activity data of FeO•Cr2O3 in ‘FeO•(Cr, Al)2O3’ solid solution is required to precisely estimate and control the Cr–O equilibrium relation in molten Fe–Cr when the alloy is produced in the furnace lining by Al2O3 refractories. In the present work, crucibles made of ‘FeO•(Cr, Al)2O3’ solid solution were equilibrated with molten Ag under CO–CO2 gas mixture at 1873 K to determine the activity of FeO•Cr2O3 in the solid solution.