在精炼处理和连铸阶段采集的低碳铝和硅镇静钢试样中非金属夹杂物的性质分析

非金属夹杂物的数量、分布、尺寸和化学成分对钢的性能有直接影响。通过控制这些夹杂物的尺寸和化学成分可以生产出优质产品。区分夹杂物的性质和控制夹杂物的形成对钢的清洁度十分重要。通过检验非金属夹杂物的化学成分可以预测夹杂物在钢中的性能。为了研究夹杂物的化学成分、尺寸和分布，某钢厂在二次精炼和连铸阶段采集了低碳铝和硅镇静钢的试样。试样用扫描电子显微镜（SEM）采用EDS系统进行分析。通过分析结果可以判定夹杂物的性质，分析精炼过程对减少夹杂数量和减小比表面积的效果。还可以确定处理后残留的夹杂对钢的性能和连铸过程（浸入式水口的堵塞）的影响大小。

Study of the Nature of Non-Metallic Inclusions in Samples of Aluminum and Silicon Killed Low Carbon Steels,Collected in the Refining Treatment and Continuous Casting Stages

The amount,distribution,size and chemical composition of non -metallic inclusions have a direct influence on steel properties.By controlling size and chemical composition of these inclusions,it is possible to get a product with good quality. The identification of the nature and the control of inclusion formation are very important for steel cleanness.The behavior of these inclusions is predictable,in some extent,by the determination of the chemical composition of non -metallic phases that form such inclusions. With the objective of studying the chemical composition,the size and the distribution of such inclusions, samples of aluminum and silicon killed low carbon steels were collected in a national steel industry in the secondary refining and continuous casting stages. These samples were analyzed in the scanning electron microscope (SEM) coupled to an energy dispersive analysis system(EDS).From the results,it was possible to evaluate the nature of inclusions and to analyze the effectiveness of the refining process in the reduction of the number and area fraction of the inclusions.It was also possible to verify that the inclusions that remained after treatment,are less damage both to the steel properties as to the continuous casting pro-cess(clogging of the submerged valve).