In this work, 37 industrial trials were conducted to examine the effect of Ca treatment on inclusion formation and transformation. The samples were taken from tundish and separated into three series based on their compositions. Three correlations between the steel chemistries and the amount as well as the composition of inclusions were determined through inclusion analysis using an automated SEM-EDS system and with the help of a segregation model. First, a modified Ca treatment index was introduced which correlated the composition of modified calcium aluminates to Ca, S, and Al content in the system. For modified Ca treatment index higher than 0.5, the calcium aluminates were found to contain more than 50 wt pct liquid phase. The second index was dimensionless Ca which signifies that the amount of CaS inclusions in a system depends on the thermodynamics stability of CaS. It was used to estimate the area fraction of CaS inclusions. The third index was related to the control of MnS inclusion formation using Ca treatment and it was found that the Ca, S and Mn contents can be used to predict the level of success of MnS inclusion control. Further, the phase of steel may have an impact on MnS inclusion formation. A method of integrating the correlations between steel chemistries and calcium aluminate, CaS, and MnS inclusions to determine the overall success in inclusion control was proposed, which has the potential of predicting the optimum Ca content.

在这项工作中，进行了 37 项工业试验来检验 Ca 处理对夹杂物形成和转化的影响。样品取自中间包并根据其成分分为三个系列。通过使用自动 SEM-EDS 系统的夹杂物分析和偏析模型的帮助，确定了钢化学成分与夹杂物的数量和组成之间的三个相关性。首先，引入了改性钙处理指标，该指标将改性铝酸钙的组成与系统中的钙、硫和铝含量相关联。对于高于 0.5 的改性钙处理指数，发现铝酸钙含有超过 50 wt pct 的液相。第二个指标是无量纲 Ca，表示系统中 CaS 夹杂物的数量取决于 CaS 的热力学稳定性。它用于估计 CaS 夹杂物的面积分数。第三个指标与使用 Ca 处理控制 MnS 夹杂物的形成有关，发现 Ca、S 和 Mn 含量可用于预测 MnS 夹杂物控制的成功程度。此外，钢的相可能对 MnS 夹杂物的形成有影响。提出了一种综合钢化学成分与铝酸钙、CaS 和 MnS 夹杂物之间的相关性来确定夹杂物控制总体成功率的方法，该方法具有预测最佳 Ca 含量的潜力。第三个指标与使用 Ca 处理控制 MnS 夹杂物的形成有关，发现 Ca、S 和 Mn 含量可用于预测 MnS 夹杂物控制的成功程度。此外，钢的相可能对 MnS 夹杂物的形成有影响。提出了一种综合钢化学成分与铝酸钙、CaS 和 MnS 夹杂物之间的相关性来确定夹杂物控制总体成功率的方法，该方法具有预测最佳 Ca 含量的潜力。第三个指标与使用 Ca 处理控制 MnS 夹杂物的形成有关，发现 Ca、S 和 Mn 含量可用于预测 MnS 夹杂物控制的成功程度。此外，钢的相可能对 MnS 夹杂物的形成有影响。提出了一种综合钢化学成分与铝酸钙、CaS 和 MnS 夹杂物之间的相关性来确定夹杂物控制总体成功率的方法，该方法具有预测最佳 Ca 含量的潜力。