Combined Effects of EMBr and SEMS on Melt Flow and Solidification in a Thin Slab Continuous Caster

Changjun Wang,Baokuan Li,Zhongqiu Liu

doi:10.3390/met11060948

Abstract

Electromagnetic fields have emerged as powerful tools for addressing current problems in thin slab continuous casting processes in the iron and steel industry. Substantial studies have been undertaken on the fundamental effects of electromagnetic brakes (EMBr) and strand electromagnetic stirring (SEMS). However, little attention has been focused on melt flow and solidification in a thin slab continuous caster with the simultaneous application of an EMBr and SEMS. The present study aimed to predict transient fields in the caster using a large eddy simulation and an enthalpy-porosity method. The electric potential method was applied in the braking process, and the conductivity change with solidification was considered. The suppressive effect on the intensity of the nozzle jet, the balance effect on the mold flow, and a dispersion effect could be observed. The dispersion effect was a novel finding and was beneficial to a flatter nozzle jet. In contrast, SEMS caused a highly turbulent flow in the strand. A large vortex could be observed in the casting direction. The solidified shell became more uniform, and the solidification rate became obviously slower. These findings supported the view that a high-quality thin slab can be produced by the application of an EMBr and SEMS.

Highlights

Electromagnetic fields have emerged as powerful tools for addressing current problems in thin slab continuous casting processes in the iron and steel industry
The results showed that neglecting advective latent heat due to the motion of the solidified shell might lead to overestimating the shell thickness
The magnitude of the exterior magnetic field generated by the electromagnetic brake (EMBr) in Tesla (T)

Summary

Introduction

Electromagnetic fields have emerged as powerful tools for addressing current problems in thin slab continuous casting processes in the iron and steel industry. Little attention has been focused on melt flow and solidification in a thin slab continuous caster with the simultaneous application of an EMBr and SEMS. The solidified shell became more uniform, and the solidification rate became obviously slower These findings supported the view that a high-quality thin slab can be produced by the application of an EMBr and SEMS. Electric-sheet steel, which should have high magnetic induction and low core loss [5], is mainly produced by Wuhan Iron & Steel In response to these problems and potential challenges, the application of electromagnetic fields [6] is an attractive method, as the parameters of the fields can be adjusted during production. Electromagnetic brake (EMBr) systems have been widely implemented in slab casters to stabilize the liquid melt flow, which greatly affects steel surface quality. Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations

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Conclusion