Equilibrium Relations between the Liquid Iron Alloys and the Deoxidation Products Resulting from Mn-Si-Al Complex Deoxidation

Abstract

The equilibrium relations between the liquid iron alloys of Fe-Mn-Si-Al-O system and the deoxidation products were studied.
Assuming that the products formed during the complex deoxdation with Mn-Si-Al alloys consisted of MnO, SiO₂, and Al₂O₃, the activities of the constituents in the MnO-SiO₂-Al₂O₃ system were determined thermochemically.
Using these results, the equilibrium relations between MnO-SiO₂-Al₂O₃ oxides and liquid iron were estimated at the condition of %Mn+%Si=1.
At the same time, the measurements on the equilibrium between the liquid iron alloys and the oxide inclusions were carried out at the melting temperature of the iron alloys, approximately 1535°C. The deoxidation products were trapped directly underneath the solid-liquid interface of metal without any contamination by the container material.
The experimental results agreed fairly well with the thermochemical calculation.