1992 年 78 巻 4 号 p. 564-571
Nitrogen and sulfur distribution ratios between CaO-Al2O3 slag and Fe-0.000133 mass% Al alloys were measured in the temperature range of 1823 to 1923 K, using Al2O3 and CaO crucibles. The distribution ratios under a CaO crucible were higher than those under an Al2O3 crucible, and increased with an increase of Al content. Nitride and sulfide capacities defined by CN3-=(mass% N)·PO23/4/PN21/2 and CS2-=(mass% S)·PO21/2/PS21/2, respectively, which were obtained by using the reported values for activity of Al2O3, agreed well those directly measured in a gas-slag experiment under an Al2O3 curcible, but disagreed with those under a CaO crucible. Activities of Al2O3 in the CaO-Al2O3 melts saturated with CaO were evaluated based on the results in the gas-slag experiments.