Calcium and magnesium deoxidation in Fe-Ni and Fe-Cr alloys equilibrated with CaO-Al2O3 and CaO-Al2O3-MgO slags

Abstract

Calcium and magnesium deoxidation equilibria in Fe-20 to 60mass%Ni, Fe-10 to 40mass%Cr and Fe-18mass%Cr and 8 mass% Ni alloys saturated with CaO-Al2O3 and CaO-Al2O3-MgO slags have been studied at 1 873 K using CaO, Al2O3 and MgO crucibles. Based on these results, the interaction coefficients between Ca and O and between Mg and O are estimated for Fe-Ni, Fe-Cr and Fe-Ni-Cr alloys. The solubilities of CaO and MgO calculated by using these interaction coefficients are compared with the observed values. The phase stability regions in the Fe-40mass%Ni-Al-O-M and the Fe-20mass%Cr-Al-O-M (M=Ca and Mg) systems are presented at 1 873 K.