Effect of MgO content and CaO/Al2O3 ratio on melting temperature and viscosity of CaF2–CaO–Al2O3–MgO slag for electroslag remelting

Release time:2024-11-22 Hits:

First Author:Pengfei Wang

Correspondence Author:Wei Gong

Co author:Zhouhua Jiang,Xingtong Li,Yu Zhang

Journal:Ceramics International

Volume:50

DOI number:10.1016/j.ceramint.2024.07.070

Place of Publication:England

Abstract:During electroslag remelting (ESR), high MgO contents are typically added to CaF2–CaO–Al2O3 slag to control magnesium content in iron- and nickel-based alloys. The melting temperature and viscosity of ESR slag are pivotal for energy consumption, production efficiency, smooth operation, and ingot quality. However, there is currently a notable scarcity of research on the melting temperature and viscosity of CaF2–CaO–Al2O3–MgO slag with high MgO levels. Thus, the melting temperatures and viscosity of CaF2–CaO–Al2O3–MgO slags with varying MgO contents and CaO/Al2O3 (C/A) ratios were investigated. The results show that as the MgO content increases from 7.83 % to 13.18 %, the final precipitation content of the MgO phase significantly increases, resulting in an increase in the melting temperature from 1306 ℃ to 1319 ℃. With the increase in the C/A ratio from 0.86 to 1.16, the precipitation completion temperatures of the Ca12Al14F2O32 and MgO phases significantly decrease and the MgAl2O4 phase transforms into the CaO phase. Hence, the melting temperature decreases from 1329 ℃ to 1314 ℃. Further increasing the C/A ratio to 1.40, the final precipitation content of the CaO phase increases, resulting in a decrease in the melting temperature from 1314 ℃ to 1282 ℃. Moreover, as the MgO content and C/A ratio increase, the slag viscosity exhibits different change trends within various temperature ranges. This depends on which of the depolymerization of the slag structure and the precipitation and clustering of the MgO phase has a greater effect on the slag viscosity.

Funded by:General project of National Natural Science Foundation of China

Key Words:CaF2− CaO–Al2O3–MgO slag, Melting temperature, Viscosity, MgO content, CaO/Al2O3 ratio

Indexed by:SCI JCR Q1

Discipline:Engineering

Document Type:JCR 一区

First-Level Discipline:Metallurgical Engineering

Page Number:36829–36837

ISSN No.:0272-8842

Translation or Not:no