Abstract
A comprehensive transient model is developed to study the effect of electrode rotation on the evolution of metal pool profiles and the solidification quality of ESR ingots. Magnetohydrodynamic flow, heat transfer, solidification, and electrode melting are considered simultaneously in the model. The growth of the ESR ingot is predicted using the dynamic layering method. The numerical results show that the productivity reaches a maximum of 15.97% at the rotating speed of 40 rpm without increasing power. With the increasing rotating speed, the maximum temperature of the melt decreases, and the temperature distribution becomes more uniform. Compared with the static one, the pool profiles are flattened by −1.19%, −8.52%, and 12.44% at the rotating speeds of 20, 40, and 60 rpm, respectively. The metal pool profile was improved remarkably, but only at the higher speed (i.e., 60 rpm). The effect of rotating speed on the metal pool profile depends on the competition between the melting rate and slag temperature. Meanwhile, the local solidification time and the secondary dendrite arm spacing are slightly improved at lower rotating speeds but are significantly worse at higher rotating speeds.
Highlights
Electroslag remelting (ESR) is an essential secondary refining process for producing high-quality steels, which are widely used in aerospace, energy, and other vital fields
The process suffers from a deep V-shaped metal pool profile, which is prone to severe segregation defects and subsequently poor performance of the ESR ingots [7]
The solidification quality of an ingot is primarily dependent on the local solidification time (LST), which is defined as the residence time of the metal between the liquidus and solidus isotherms [2]
Summary
Electroslag remelting (ESR) is an essential secondary refining process for producing high-quality steels, which are widely used in aerospace, energy, and other vital fields. The process suffers from a deep V-shaped metal pool profile, which is prone to severe segregation defects and subsequently poor performance of the ESR ingots [7]. This profile results from the heat accumulation in the ingot center, closely related to the concentrated dripping of metal droplets. The rotation accelerates the Metals 2021, 11, 1675 the flow pattern in the slag layer, strengthening the convective heat exchange between the slag and electrode, and between the slag and mold. The 3D-calculated domain includes the molten slag layer, liquid metal pool, and solidified ingot. Volume fraction (α) thermal expansion coefficient (β) property (φ) electrical conductivity (σ) density (ρ) magnetic diffusivity (η) effective viscosity (μe f f ) turbulent viscosity (μt) surface tension coefficient (σij) curvature (κ)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
