Equilibrium between Liquid Iron-chromium Alloy and Silica-saturated Slag.

Abstract

Recently, physico-chemical researches have been done by many laboratories for stainlesssteel making practice. Chromium and silicon are the most important elements in acidic steelmaking but it is not well known how they react eacl other. So long as the structures of slag are not fully understood physically and chemically, the various reactions between theacidic slag and the liquid iron-chromium alloy will not be solved definitely. However, theauthors tried to observe accurately these various reactions and to obtain fundamental datafor acidic steel making practice.
Although generally chromic oxide is dissolved in ionic state in the silica saturated slag, and chromium ion could not be measured directly in the present work its reactivity, characterand component were examined from experimental data, and compared with the resultsof other works.
The relation between the distribution of chromium in two phases and FeO in slag showsthat the oxide of chromium in the slag was dissolved, with its component nearly equal tothat of CrO.
The equilibrium data for silicon and chromium with acidic slag showed that the follomingchemical reaction occurred in two phases, log K'=5738/T-3·179
In the range of above 5 weight per cent chromium, the experimental data agreed with thevalues, calculated values using the equilibrium formula, but under 5 weight per cent, theexperimental data were smaller than the calculated.
The solubility of oxygen showed a good agreement with the previous data in the rangeabove 3 per cent chromium but under that the experimental value was higher than in theother reports.