Enhancing the Quality of Electrotechnical Steel Grade Slab Billets via Electromagnetic Stirring in the CCM Secondary Cooling Zone

Electromagnetic stirring (EMS) of the liquid phase of billets is one of the most technologically advanced methods to enhance the macrostructure quality of continuously cast slabs produced on high-performance continuous casting machines (CCMs). Under the influence of EMS, a forced movement of the melt is created relative to the crystallization front. The temperature gradient across the cross-section of the slab and the chemical composition of the steel are stabilized via heat and mass transfers. A project was implemented at Novolipetsk Iron and Steel Works to equip a slab CCM with an EMS system in the secondary cooling zone of a continuously cast ingot (CCI). This paper presents the industrial development results of the teeming electrotechnical steel technology using the EMS system. Furthermore, the key aspects of stirring and technological parameters of teeming electrotechnical steel are presented. The effect of EMS on the quality of a CCI is confirmed in terms of crystallization structure variations with an increase in the zone of equiaxed crystals by more than twice in comparison with the typical teeming practice. Furthermore, it has been established that using EMS can effectively influence liquid steel and considerably enhance the quality of the CCI macrostructure and the uniformity in the properties of finished rolled products.