Present situation and prospect of permanent magnet stirring during billet continuous casting
PENG Jian-fei1, ZENG Jie1, WANG Wan-lin1, CHEN Bo-tao2, YANG Wen-zhi2
1. School of Metallurgy and Environment, Central South University, Changsha 410083, Hunan, China; 2. Quality Department Xiangtan Iron and Steel Co., Ltd., Hunan Valin, Xiangtan 411101, Hunan, China
Abstract：Electromagnetic stirring has become an important technique to improve billet quality in continuous casting process. Compared with the traditional three-phase AC electromagnetic stirring (EMS), the permanent magnet stirring (PMS) based on sintered NdFeB material has the advantages of higher magnetic induction intensity, lower power consumption and simpler structure. The technical characteristics of electromagnetic stirring and permanent magnet stirring are compared and the present application situation of mold and final permanent magnet stirring during billet continuous casting is introduced. It was reported that the mold permanent magnet stirring can effectively improve the surface and internal quality of the billet, reduce the hole defects on the surface, and improve the central porosity and central carbon segregation of the billet. In addition, permanent magnet stirring was applied in the final solidification position of high carbon steel continuous casting rectangular billet. It was found that the center carbon segregation index of the billet decreases obviously with the increase of the rotating speed of PMS, and the energy consumption of PMS per ton of steel was only about 15% of that of traditional EMS.
ZENG J, CHEN W Q, YANG Y D, et al. A review of permanent magnet stirring during metal solidification[J]. Metallurgical and Materials Transactions B, 2017, 48(6), 3083.
[6]
Bojarevics A, Beinerts T, Gelfgat Y, et al. Permanent magnet centrifugal pump for liquid aluminium stirring[J]. International Journal of Cast Metals Research, 2016, 29(3): 154.
[7]
Vivès C. Elaboration of metal matrix composites from thixotropic alloy slurries using a new magnetohydrodynamic caster[J]. Metallurgical Transactions B, 1993, 24(3): 493.
BojareviAČs A, Beinerts T, Sarma M, et al. Arrays of rotating permanent magnet dipoles for stirring and pumping of liquid metals[J]. Journal for Manufacturing Science and Production, 2015, 15(1): 35.
[26]
ZOU J, ZHANG H, QIAO X, et al. Research on grain refinement and its mechanism of pure aluminum under a novel permanent magnet stirring[J]. Journal of Materials Research and Technology, 2021, 15: 5894.
[27]
WANG W L, PENG J F, ZENG J, et al. Evolution of solidification structure, primary phase and wear properties of Sn-11wt%Sb alloy ingots under permanent magnet stirring[J]. Philosophical Magazine, 2021, 101(11):2273.
Kawami A, Maruta Y, Kameko S, et al. Improvement of surface quality by rotating magnet stirrer in the mold on c. c. bloom[J]. Trans of ISIJ, 1982, 22(3): B46.
[30]
Hagiwara T, Taki M, Kimura K, et al. Improvement of internal quality by rotating magnet stirrer in the mold on c. c. bloom[J]. Trans of ISIJ, 1982, 22(3): B47.
[31]
Matsuura Y. Recent development of Nd-Fe-B sintered magnets and their applications[J]. Journal of Magnetism and Magnetic Materials, 2006, 303(2):344.
ZENG J, CHEN W Q, ZHANG S. Experimental study of molten metal flow and numerical simulation of magnetic field during permanent magnet stirring and its application in continuous casting[J]. Metallurgical Research and Technology, 2016, 113(6):609.
[34]
ZENG J, CHEN W Q, ZHANG S L, et al. Development and application of final permanent magnet stirring during continuous casting of high carbon rectangular billet[J]. ISIJ International, 2015, 55(10):2142.
[35]
ZENG J, CHEN W Q, YANG Y D, et al. Effect of permanent magnet stirring on internal quality of steel[J]. Ironmaking and Steelmaking, 2018,45(6):576.
2022, Vol. 41 
