结晶器电磁搅拌对20CrMnTiH钢方坯树枝晶生成的影响  

Effect of mold electromagnetic stirring on dendrite generation in 20CrMnTiH steel square billet

作　　者：岳峰 刘佳伟 伍帅 卫晓辉 Yue Feng;Liu Jiawei;Wu Shuai;Wei Xiaohui(Collaborative Innovation Center of Steel Technology,University of Science and Technology Beijing,Beijing 100083,China;China Academy of Machinery Beijing Research Institute of Mechanical&Electrical Technology Co.,Ltd.,Beijing 100083,China;MCC Huatian Nanjing Engineering&Technology Corporation,Nanjing 210019,China)

机构地区：[1]北京科技大学钢铁共性技术协同创新中心,北京100083 [2]中国机械总院集团北京机电研究所有限公司,北京100083 [3]中冶华天南京工程技术有限公司,江苏南京210019

出　　处：《锻压技术》2025年第3期70-76,共7页Forging & Stamping Technology

摘　　要：针对国内某钢厂20CrMnTiH钢的160 mm×160 mm方坯,研究结晶器电磁搅拌(M-EMS)电流强度对树枝晶生成的影响。结果表明,二次枝晶间距(SDAS)的增加与枝晶离钢坯表面的距离成正比。不使用结晶器电磁搅拌时,距离方坯表面2 mm位置SDAS为23μm,距离方坯表面26 mm位置的SDAS增加至75μm。使用M-EMS会增加SDAS,SDAS随着M-EMS电流强度的增加而增加。M-EMS电流强度由150 A增加至320 A时,平均SDAS由50.8μm增加至54.9μm。M-EMS会导致距离方坯表面8 mm位置的二次枝晶断裂,随着搅拌强度的增加,断裂的二次枝晶越多。M-EMS使方坯柱状晶区的一次枝晶向同一方向倾斜生长,一次枝晶倾角随着M-EMS电流强度的增加而增加。通过一次枝晶倾角估算凝固前沿的钢液流速,M-EMS电流强度为150 A时,一次枝晶倾角为23.2°,钢液流速为0.146 m·s^(-1);电流强度为320 A时,一次枝晶倾角为27.8°,钢液流速为0.358 m·s^(-1)。For a 160 mm×160 mm square billet of 20CrMnTiH from a domestic steel mill,the effect of current intensity for mold electro-magnetic stirring(M-EMS)on the dendrite generation was studied.The results demonstrate that the increase in secondary dendrite spac-ing(SDAS)is proportional to the distance of dendrites from the billet surface.In the absence of mold electromagnetic stirring,the SDAS is 23μm at a distance of 2 mm from the billet surface,and increased to 75μm at a distance of 26 mm from the square billet surface.Using M-EMS will increase the SDAS,and the SDAS increases with the increasing of the current intensity for M-EMS.When the current in-tensity of M-EMS increases from 150 A to 320 A,the average SDAS increases from 50.8μm to 54.9μm.M-EMS will cause the secondary dendrites at 8 mm from the square billet surface to break.As the stirring intensity increases,the number of broken secondary dendrites will increase.M-EMS causes the primary dendrites in the columnar grain zone of the square billet to grow obliquely in the same direction,and the inclination angle of the primary dendrites increases with the increasing of the current intensity for M-EMS.The flow velocity of the molten steel at the solidification front can be estimated through the inclination angle of the primary dendrites.When the M-EMS current intensity is 150 A,the inclination angle of the primary dendrites is 23.2°and the flow velocity of the molten steel is 0.146m·s^(-1).When the current intensity is 320 A,the inclination angle of the primary dendrites is 27.8°and the flow velocity of the molten steel is 0.358m·s^(-1).

关 键 词：20CRMNTIH钢 结晶器电磁搅拌 电流强度 一次枝晶 二次枝晶 

分 类 号：TF777.2[冶金工程—钢铁冶金]