Effect of Melting Rate on Solidification Process of High Filled Ratio 06Cr18Ni11Ti Electroslag Remelting Ingot

Abstract

This study focuses on the transient electroslag remelting process of 06Cr18Ni11Ti ingots with high filled ratio. By establishing a multiphysics and multiphase coupled model of the ESR process， the influence of melting rate on electromagnetic， heat transfer， fluid flow， and solidification behaviors during the ESR process was investigated. The results indicate that under different melting rates， the current paths are generally consistent， with a obvious skin effect. The temperature inside the crystallizer exhibits a parabolic distribution with significant temperature gradients. As the melting rate increased from 5 kg/min to 7 kg/min， the current density， Lorentz force， and Joule heating increased by 16.2%， 37.7%， and 63.3%， respectively. The maximum temperature of the slag pool increased from 1 902 K to 2 058 K. Both the slag and molten pools exhibit pairs of oppositely directed vortices， with flow becoming more intense with the increasing of melting rate. Under the conditions studied in this paper， increasing the melting rate leads to deepening of the molten pool and prolonging the local solidification time of the ingot. When the melting rate is 5 kg/min， the depth of the molten pool is between 1/2 and 1/3 of the mold diameter and the local solidification time is shortest， which helps to ensure the good density and crystallization quality of the ingot.

Keywords

• electroslag remelting； melting rate； high filled ratio； 06cr18ni11ti steel； solidification process