Effect of roller-typed electromagnetic stirring and its coils location on solidification behavior of a slab casting
XIAO Hong1,2, WANG Pu2, ZHENG Qing3, LIU Shun1, CHEN Xi-qing2, ZHANG Jia-quan2
1. Electromagnetic Center, Hunan Zhongke Electric Co., Ltd., Yueyang 414000, Hunan, China; 2. School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China; 3. 4th Steelmaking and Rolling General Works, Maanshan Iron and Steel Co., Ltd., Maanshan 243000, Anhui, China
Abstract：Roller-typed electromagnetic stirring (R-EMS) is one of effective measures to control the as-cast macrostructure and prevent the occurrence of mid-way cracks for slab casting. To reveal the mechanism and the frequently attendant asymmetrical solidification along with white band, the solidification behavior of a slab casting with section of 1 600 mm×230 mm has been numerically studied upon the applications a roller-typed electromagnetic stirrer, for which a coupled electro-magnetic, fluid flow, heat transfer and solidification model has been adopted by segment to segment consecutive calculation. It has been shown that it is the tangential forces produced by R-EMS ahead of the solidification frontier and its effect on the local enriched fluid flow and temperature which promote the columnar to equiaxed crystal transformation, and eliminate the occurrence condition of mid-way cracks from as-cast structure. It is found, there exists an obvious end effect for travelling wave magnetic field in the cross section while the EMS roller being in alignment with the slab geometrically. To be exact, the magnetic induction intensity and its induced force are much larger in the other side of the slab as compared with the initial side, which should be the reason of its final asymmetrical solidification structure. However, the asymmetrical behavior can be partly alleviated by an offset location of the roller coils toward the initial side. For the present format of slab casting, the magnetic induction intensity and the final as-cast structure shows a nearly symmetrical ones with a coil offset value around 150 mm. Finally, it has been addressed that the white band of negative segregation, a scour marks left by the intensified fluid flow due to electromagnetic force, shows no unacceptable effect on the finished products presently, but should be given attention in the future for its change in the following hot rolling products and any possible other disadvantage.
肖红, 王璞, 郑晴, 刘顺, 陈希青, 张家泉. 辊式电磁搅拌线圈位置对板坯凝固行为的影响[J]. 钢铁, 2023, 58(3): 79-88.
XIAO Hong, WANG Pu, ZHENG Qing, LIU Shun, CHEN Xi-qing, ZHANG Jia-quan. Effect of roller-typed electromagnetic stirring and its coils location on solidification behavior of a slab casting[J]. Iron and Steel, 2023, 58(3): 79-88.
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2023, Vol. 58 
