Effect of CaO/Al2O3 on structure, viscosity, and surface tension of electroslag remelting-type CeO2-bearing slag

作者：Zheng, Ding-li; Ma, Guo-jun^*; Zhang, Xiang; Liu, Meng-ke; Xu, Ju

来源：JOURNAL OF IRON AND STEEL RESEARCH INTERNATIONAL, 2023, 30(4): 717-725.

DOI：10.1007/s42243-022-00844-x

• Electroslag remelting
• CeO2-bearing slag
• CaO/Al2O3
• Structure
• Viscosity
• Surface tension

The structure of electroslag remelting-type CaF2-CaO-Al2O3-CeO2 slag with various CaO/Al2O3 mass ratios and its correlation with viscosity and surface tension were investigated. The Raman analysis of the slag shows that with increasing CaO/Al2O3 mass ratio from 0.70 to 1.29 in the slag, the polymerization degree of the slag decreased, which was because more complex [AlO4]-tetrahedral units of Q(Al)(3) and Q(Al)(4 )were depolymerized to form relatively simpler structural units Q(Al)(0), Q(Al)(0), and Q(Al)(2), and the excess oxygen ions introduced by CaO promoted the transformation of [AlO4]-tetrahedral units to [AlO6]-octahedral units. Increasing CaO/Al2O3 mass ratio has an obvious effect on reducing the viscosity and activation energy for viscous flow of the slag, resulting from the depolymerization of the slag. Owing to the decrease in the polymerization degree and the increase in the total Ca2+ content of the slag, the surface tension of the slag increases with the increase in CaO/Al2O3 mass ratio. The surface tension of the slag changes slightly with the temperature, irrespective of CaO/Al2O3 mass ratio from 0.70 to 1.29 in the slag.