转炉流程轴承钢连铸坯非金属夹杂物的行为

探讨了BOF-LF-VD-CC流程生产的轴承钢连铸坯非金属夹杂物的物性、分布、特点,并通过示踪剂追踪分析了轴承钢夹杂物的来源,为轴承钢夹杂物的去除,提高转炉流程轴承钢质量提供了依据.研究表明,该生产流程可以获得TO]的平均值为9.3×10-4%;显微夹杂体积分数为0.031%;>50μm的大型夹杂为1.5 mg/10 kg的洁净度较高的轴承钢连铸坯.夹杂物主要为<5μm的显微夹杂,它的分布特点决定了连铸坯中夹杂物的分布特点,显微夹杂主要是多元素复合脱氧产物与中间包液面二次氧化产物吸附集聚形成的复合物,其次是结晶器液面对钢液的污染,钢包液面影响较小.

Behavior of Non-Metallic Inclusions in Casting Slab of BOF Bearing Steel

The distribution and characteristics of nonmetallic inclusion in the bearing steel slabs melted and cast in the process of BOF-LF-VD-CC were explored, with a tracer used to find the origin of inclusion. The aim is to provide a reference for getting rid of inclusions to improve the quality of BOF bearing steel. The results showed that in the high-cleanness slabs the mean value of TO] is 9.3 × 10^-4 wt%, the micro inclusions are 0.031 vol% and the large-size (>50 μm) inclusions are 1.5 mg/10 kg, and most of the inclusions are micro inclusions (<5 μn) whose distribution feature determines the distribution feature of inclusions in casting slab. The micro inclusions are mainly the compounds formed via the adsorption/aggregation of multielement deoxidized compounds and secondarily deoxidized products on tundish liquid level. The rest is mainly the contaminants present in molten steel, which are coming from the liquid level in mold. The liquid level in tundish affects slightly the molten steel.