Cao Kun,Qu Shuo,Liu Zhen,et al.Effect of Mechanical Reduction Process of 22MnB5 Steel Slab[J].Special Steel,2026,47(02):100-107. DOI: 10.20057/j.1003-8620.2025-00173.
Effect of Mechanical Reduction Process of 22MnB5 Steel Slab
To address the internal quality issues of 1 400 mm × 300 mm thick 22MnB5 steel slabs, a dynamic mesh mechanical soft-reduction model for slab solidification was developed. This model integrates multiple physical fields, including fluid flow, heat transfer, solidification, and solute transport, to analyze the effects of reduction amount and reduction zone on slab internal quality. The results show that mechanical soft reduction can effectively mitigate centerline segregation, and the improvement becomes more pronounced with increasing reduction amount. In particular, when a 10 mm reduction is applied, centerline segregation is significantly alleviated, with a notable decrease in the segregation ratio. Furthermore, the selection of reduction position is critical. Under a casting speed of 1.0 m/min and a superheat of 20 °C, applying reduction in the region 14 m-18 m below the mold meniscus, where the solid fraction is 0.05-0.45, exacerbates segregation. Conversely, when reduction is applied in the region 16-20 m below the meniscus, corresponding to a solid fraction of 0.20-0.95, solute transport is promoted, thereby improving segregation in the slabs.
关键词
Keywords
references
Fachinotti V D , Le Corre S , Triolet N , et al . Two-phase thermo-mechanical and macrosegregation modelling of binary alloys solidification with emphasis on the secondary cooling stage of steel slab continuous casting processes [J]. International Journal for Numerical Methods in Engineering , 2006 , 67 ( 10 ): 1341 - 1384 .
Zhu L G , Kumar R V . Shrinkage of carbon steel by thermal contraction and phase transformation during solidification [J]. Ironmaking & Steelmaking , 2007 , 34 ( 1 ): 71 - 75 .
Murao T , Kajitani T , Yamamura H , et al . Simulation of the center-line segregation generated by the formation of bridging [J]. ISIJ International , 2014 , 54 ( 2 ): 359 - 365 .
Vynnycky M , Saleem S , Fredriksson H . An asymptotic approach to solidification shrinkage-induced macrosegregation in the continuous casting of binary alloys [J]. Applied Mathematical Modelling , 2018 , 54 : 605 - 626 .
Ogibayashi S , Yamada M , Yoshida Y , et al . Influence of roll bending on center segregation in continuously cast slabs [J]. ISIJ International , 1991 , 31 ( 12 ): 1408 - 1415 .
Yim C H , Park J K , You B D , et al . The effect of soft reduction on center segregation in C.C. slab [J]. ISIJ International , 1996 , 36 : S231 - S234 .
Tsuchida Y , Nakada M , Sugawara I , et al . Behavior of semi-macroscopic segregation in continuously cast slabs and technique for reducing the segregation [J]. Transactions of the Iron and Steel Institute of Japan , 1984 , 24 ( 11 ): 899 - 906 .
Qi X X , Zhang G , Jia Q . Studies on technological parameters of optimal soft reduction about superwide slab caster [J]. Advanced Materials Research , 2011 , 194-196 : 207 - 212 .
Xu Z G , Wang X H , Jiang M . Investigation on improvement of center porosity with heavy reduction in continuously cast thick slabs [J]. Steel Research International , 2017 , 88 ( 2 ): 1600061 .