1. Steelworks Factory, JUNENG Special Steel Co., Ltd, Shouguang 262700, Shandong, China; 2. State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, Beijing 100083, China
Abstract：In order to study the aggregation of non-metallic inclusions in the continuous casting process of bearing steel, a flow-solidify-coupled model of solidification process was established. The migration behavior of inclusions in the casting process was studied by means of numerical simulation combined with factory tests. The results show that, as the comparison of casting varieties, such as mould sections, the M-EMS, and SEN types, the parameters of bigger sections, stronger M-EMS stirring and many-side-port SEN nozzles, are more favorable to improve the inclusions below 10 μm in the bloom, and the inclusions of 5-10 μm level are most easily captured by the raw casting shell. Results also show that, high number density of microscopic inclusion groups in tundish, which are below 5 μm, will promote the collision and migration during the pouring process, resulting in an accumulation of inclusion groups with 20-30 μm in the bloom, but has little effect on large size inclusion groups, which are above 50 μm. The inclusion groups with that macro size level in the bloom are mainly originated from tundish directly. These results are of great significance to clarify the origin of inclusions and improve the fatigue life of bearing steel.
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2022, Vol. 41 
