Improved Removal Efficiency of Submicron Inclusions in Non-oriented Silicon Steel during RH Process

Abstract

To improve the removal efficiency of such submicron inclusions, we designed an argon blowing method for an RH facility based on mathematical simulations. The effect of the argon blowing on the liquid steel flow and the movement of submicron inclusions was studied using the k-ε flow model coupled with the DPM model for inclusion movement based on fluid computational dynamics in FLUENT. It was found that a more uniform argon flow can be achieved in the up-leg snorkel with a new nozzle position and inner diameter, which resulted in a favorable up-lifting and mixing movement. The new design also increased the circulation rate of molten steel in the RH chamber. The increased turbulent kinetic energy and turbulent dispersing rate enhanced the collision probability of submicron inclusions, which results in an improved removal for 0.5–1 µm inclusions. The proposed RH facility could increase the removal rate of submicron inclusions from the original 57.1% to 66.4%, which improves the magnetic properties of non-oriented silicon steel.

Keywords

RH treatment / argon blowing method / model optimization / submicron inclusions / numerical simulation