Measurement of Interaction Parameter between Cu and Al in Molten High Al Steel

Abstract

The interaction parameter between Cu and Al in molten iron containing high levels of Al was measured using a chemical equilibrium technique. A molten Fe–Al alloy was equilibrated with a molten Ag–Cu alloy in an Al₂O₃ crucible at 1823 K. The activity coefficient of Cu in Fe–Al alloys was measured to be −2.33 while varying the concentration of Al in a range from 0.04–0.2 mol%. The influence of Cu on the deoxidation equilibrium of Al and O was estimated using the above interaction parameter. The results indicate that under a constant Al concentration, a contamination of several percent of Cu raises the O concentration in high Al steel.