1996 Volume 36 Issue Suppl Pages S136-S139
In order to understand the reoxidation behavior by slag in the steelmaking process, the oxygen potential of the slags in the ladle was estimated quantitatively adopting the regular solution model by Lumsden. The activity of iron oxide in slag was determined by an automatic facility employing an electro-chemical technique which incorporates stabilized zirconia as the solid electrolyte. The conversion equation for the activity of FetO has been deduced from the correlation between the measured values of FetO activity and the calculated ones by the regular solution model. The activity coefficient of FetO for the slag in refining process was estimated to be 2.308 to the mole fraction of FetO, and 0.0228 to the mass% total Fe on average.