Electromagnetic Effects on Solidification Defect Formation in Continuous Steel Casting

Understanding and reducing defects formed during continuous casting of steel are challenging because of the many inter-related, multiscale phenomena and process parameters involved in this complex process. Solidification occurs in the presence of turbulent multiphase flow, transport and capture of particles, superheat transport, and thermal-mechanical behavior. The application of electromagnetic fields provides an additional parameter to control these phenomena to reduce solidification defects. It is especially attractive because the field has the potential to be easily adjusted during casting to accommodate different casting conditions. This article briefly reviews how electromagnetic forces affect solidification defects, including subsurface hooks, particle capture, deep oscillation marks, depressions, cracks, breakouts, segregation, and shrinkage. This includes the related effects on superheat transport, initial solidification, surface quality, grain structure, internal quality, and steel composition distribution. Finally, some practical strategies regarding how to apply electromagnetics to improve steel quality are evaluated.