ABSTRACT Industrial experiments and thermodynamic calculations were performed to investigate the evolution of non-metallic inclusions during cooling and solidification of GCr15 bearing steels with different steel compositions. Non-metallic inclusions in bloom and rolled rod were characterized using the improved non-aqueous electrolysis method firstly. Inclusions in molten steel were mainly irregular MgO·Al2O3 and globular CaO–Al2O3–(MgO). Pure cluster MgO·Al2O3, MgO–Al2O3–CaS–(MnS) and MgO–Al2O3–(CaS)–MnS, CaO–Al2O3–(MgO)–CaS, MnS and cubic TiN precipitates were observed in bloom. The high-temperature heating accelerated the precipitation of MnS on the MgO·Al2O3 and more MgO–Al2O3–MnS complex inclusions were detected in rolled rod. During the continuous casting, CaO–Al2O3–(MgO) type inclusions in molten steel fully or partially transformed into MgO–Al2O3–CaS. The MgO and CaS content in inclusions increased while the CaO and Al2O3 content decreased during the transformation. Details of inclusion transformation were illustrated by thermodynamic calculations.

中文翻译：

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GCr15轴承钢冷却凝固过程中非金属夹杂物的特征与演变

摘要 通过工业实验和热力学计算，研究了具有不同钢成分的 GCr15 轴承钢在冷却和凝固过程中非金属夹杂物的演变。首次采用改进的非水电解法对大方坯和轧制棒材中的非金属夹杂物进行了表征。钢水中夹杂物主要是不规则的MgO·Al2O3和球状CaO-Al2O3-(MgO)。观察到纯团簇 MgO·Al2O3、MgO-Al2O3-CaS-(MnS) 和 MgO-Al2O3-(CaS)-MnS、CaO-Al2O3-(MgO)-CaS、MnS 和立方 TiN 沉淀物。高温加热加速了 MnS 在 MgO·Al2O3 上的析出，并且在轧制棒材中检测到了更多的 MgO-Al2O3-MnS 复合夹杂物。在连铸过程中，钢水中的 CaO-Al2O3-(MgO) 型夹杂物完全或部分转化为 MgO-Al2O3-CaS。转变过程中夹杂物中MgO和CaS含量增加，而CaO和Al2O3含量减少。通过热力学计算说明了夹杂物转变的细节。