Numerical investigation on the effect of fill ratio on macrosegregation in electroslag remelting ingot

A transient three-dimensional (3D) model was developed to understand the role fill ratio plays in the macrosegregation induced by the magnetohydrodynamic (MHD) thermosolutal convection in the electroslag remelting (ESR) process. In this model, the solution of the mass, momentum, energy, and species conservation equations are simultaneously implemented by the finite volume method with full coupling of the Joule heating and Lorentz force by solving the Maxwell's equations. Anisotropic permeability was employed to describe the directional solidification. The experimental data and the simulated data demonstrated reasonable agreement. An increase in fill ratio resulted in a larger melting rate and a deeper metal pool. The maximum positive and negative segregation indexes along the ingot centerline increased from 0.16 to 0.18 and from −0.055 to −0.071 respectively when the fill ratio was varied from 0.21 to 0.60.