Abstract：55SiCrA spring steel is prone to be affected by inner quality problems in continuous cast billets. Appropriate final electromagnetic stirring (F-EMS) can effectively improve the inner quality of the billets, however the unreasonable stirring parameters fails to improve the inner quality of the continuous casting billets, or even deteriorate the inner quality. In this paper, the influence of F-EMS parameters was studied on the inner quality of 55SiCrA billet with a section size of 150mm×150mm. The solidification condition of the casting blank under the current process was analyzed by establishing a solidification and heat transfer model, and the position of F-EMS was determined to be 8.45m-8.73m away from the meniscus. On the basis of measuring the center magnetic induction intensity of the billets under F-EMS, the matching of current and frequency is studied and the corresponding industrial tests are conducted. The results indicate that the comprehensive quality of the continuous casting billet is best when F-EMS parameter is 300A/8Hz. For billets, the average center carbon segregation index reaches 1.007, the center pipe of the continuous casting blank is improved, and the central equiaxed crystal ratio is increased.
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2020, Vol. 55 
