Abstract: Taking a steel mill Φ800 mm round billet continuous casting machine as the research object， the influence of crystallizer electromagnetic stirring current and frequency on electromagnetic torque and Q355NE steel round billet equiaxed crystal rate and carbon segregation was studied. It was found that the electromagnetic torque increased with the increase of the crystalliser electromagnetic stirring， and the increase was gradually increased. The higher the current intensity， the more significant the effect of frequency on the torque enhancement. The current intensity ranges from 0 to 200 A， the isometric crystal rate increases with the increase of current strength and electromagnetic torque， and the isometric crystal rate and electromagnetic torque is linearly related. Negative subcutaneous segregation occurs at a current intensity of 150 A. Compared to a current intensity of 50 A， a more severe positive segregation of intergranular transformation occurs at a current intensity of 150 A.

Key words: Crystallizer Electromagnetic Stirring, Electromagnetic Torque, Q355NE Billet, Equiaxial Crystal Rate, Macroscopic Segregation

摘要： 以钢厂Φ800 mm圆坯连铸机为研究对象，研究结晶器电磁搅拌电流和频率对电磁扭矩以及Q355NE钢圆坯等轴晶率和碳偏析的影响规律。研究发现，电磁扭矩随着结晶器电磁搅拌（M-EMS）电流强度的增加而增加，且增加幅度逐渐加大。电流强度越高，频率对电磁扭矩的增强效果越显著。电流强度在0~200 A时，等轴晶率随电流强度和电磁扭矩的增加而增加，且等轴晶率和电磁扭矩呈线性关系。电流强度为150 A时出现皮下负偏析，相比较于电流强度为50 A，电流强度为150 A时出现了更为严重的晶间转变正偏析。

关键词: 结晶器电磁搅拌, 电磁扭矩, Q355NE圆坯, 等轴晶率, 宏观偏析