Fe-Cr系熔融合金中の酸素の活量および溶解度

抄録

The activity of oxygen dissolved in liquid iron-chromium alloy was determined by measuring the equilibrium of the reaction between dissolved oxygen in liquid alloy and H₂-H₂O gas mixture. The experiments were carried out at 1600°C up to 30% chromium. The effect of chromium on the activity coefficient of oxygen was represented by the following equation: logf_O(%)^Cr = -8.01 ·N_Cr + 5.82 ·N_Cr^1.2,  N_Cr < 0.3,  1600°C. In the range 0∼10%Cr, the data were represented approximately by e_O^Cr=−0.047. The gas ratio of H₂-H₂O mixture in equilibrium with liquid iron-chromium alloy and solid oxide phases was measured at 1600°C up to 20% chromium. Using the data on the equilibrium gas ratio and the activity of oxygen in liquid iron-chromium alloy, the solubility of oxygen was thermodynamically calculated. The results were in good agreement with the work of Chipman⁽⁵⁾.