Application of Heat Absorption Method to Improve Quality of Large Steel Ingot

Abstract

The heat absorption method (HAM) was proposed to improve the quality of a large steel ingot. The CaO-CaF 2 inorganic material rods was used to reduce 5 K superheat of the 6-ton GCr15 molten steel. The quality of the steel ingots with and without the HAM was compared. In comparison with conventional casting, the HAM not only significantly alleviated the A-and V-segregation and the segregation levels of carbon and sulfur, but also reduced the number of inclusions and the shrinkage porosity zone in the 6-ton steel ingot. The simulation results demonstrated that the molten steel could quickly be cooled from within by the inorganic material rods, which is the main reason for the reduction of macrosegregation. Additionally, the majority of inclusions could be absorbed and removed when the liquid inorganic material floated up in the molten steel.

Improving microstructure and segregation of steel ingot by inorganic heat absorption method

“…However, the selection of the number of ladles and the interval time, as well as the control of the solute composition of the molten metal in each ladle still need further study. Li et al [30] proposed the HAM (Heat Absorption Method) through adding inorganic material rods into the liquid steel, which could effectively improve the A-and V-segregation and reduce the shrinkage porosity and inclusions in 6-ton and 5-ton steel ingot. In order to further explore the process of adding inorganic materials, we conducted a pilot test for 250 kg steel ingot.…”