中厚板钢精炼过程夹杂物的转变

 通过工业试验研究了中厚板钢LF→钙处理→RH精炼过程中夹杂物的转变规律，并对钙处理过程夹杂物转变进行了热力学计算分析。结果表明：精炼过程钢中总氧质量分数降低，夹杂物数量密度降低，夹杂物平均尺寸升高；钙处理后夹杂物为CaO-MgO-Al2O3-CaS四元系；RH破空后夹杂物转变为CaO-MgO-Al2O3三元系，夹杂物中CaO质量分数降低，Al2O3质量分数升高；热力学计算表明，钙处理后钢液可直接生成CaS，也可与钙铝酸盐夹杂物反应生成CaS，RH破空后不能生成CaS。

Evolution mechanism of inclusions in plate steel during secondary refining process

Characteristics of inclusions in plate steel refined by LF-Calcium treatment-RH process was studied by industrial experiments. Thermodynamic calculation was performed to study the evolution mechanism of inclusions during calcium treatment. It was found that the mass percent of TO] and number density of inclusions decreased,average size of inclusions increased during secondary refining processes. After calcium treatment，inclusions were in CaO-MgO-Al2O3-CaS quaternary system. After RH refining，inclusions were in CaO-MgO-Al2O3 ternary system. The mass percent of CaO of inclusions decreased and the Al2O3 content of inclusions increased during RH refining. Thermodynamic calculation results showed that CaS could form directly in molten steel as well as through the reaction between molten steel and calcium aluminate inclusions. However，the formation of CaS was not available after RH refining.