Effects of EMS on the dendritic structure and homogeneity of rail steel
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摘要: 为提升重轨钢均质性和致密性,通过试验对比分析连铸电磁搅拌对大方坯重轨钢凝固组织及均质性的影响。结果表明:无电磁搅拌工艺条件下,铸坯凝固组织无明显分区,枝晶组织致密且铸坯窄面至距离窄面80 mm区域的均质性较好,但铸坯中心偏析严重;通过取消结晶器电磁搅拌(M-EMS)并采用凝固末端电磁搅拌(F-EMS)有利于重轨钢均质性和致密性协同提升,试验铸坯中心偏析可以得到补充控制,铸坯轧制钢轨的中心偏析控制良好,轨头Mn元素偏析度极差达到0.098,致密度达到0.9764。Abstract: In order to optimize the homogeneity and compactness of rail steel, the effects of continuous casting electromagnetic stirring on the dendritic structure and homogeneity of rail steel was analyzed by industrial experiments. The results show that blooms produced without electromagnetic stirring have no obvious dendritic structure partition, the dendritic structure tends to be more compact and the homogeneity is better for the area in which from narrow surface to 80 mm below, while central segregation tends to be worse. The F-EMS is more suitable both for optimizing homogeneity and compactness than M-EMS. Central segregation control of experiment blooms could be make up, Central segregation of rails rolled from the experiment blooms is well, and the same as rail head, range value of segregation degree for Mn is 0.098, value of compactness degree is 0.9764.
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Key words:
- continuous casting /
- rail steel /
- electromagnetic stirring /
- dendritic structure /
- homogeneity /
- compactness
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表 1 不同试验工艺对应的实际磁场强度
Table 1. Actual magnetic flux density corresponding to the testing processes
T 试验工艺 实际磁场强度×10−4 强搅拌 350~400 弱搅拌 200~250 无搅拌 0 表 2 连铸电磁搅拌工艺验证试验方案
Table 2. Test program of processes verification for continuous casting electro-magnetic stirring
试验工艺 结晶器电磁搅拌
(M-EMS)凝固末端电磁搅拌
(F-EMS)工艺1 无 有 工艺2 有 无 工艺3 有 有 -
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