Microstructure Analysis of Mold Flux of Cao-SiO2-Al2O3-Na2O-MgO System for Ingot Casting

doi:10.12068/j.issn.1005-3026.2023.04.008

Abstract

Abstract: In order to clarify the influence mechanism of chemical composition change on physical properties of mold flux for ingot casting， the microstructure of CaO-SiO₂-Al₂O₃-Na₂O-MgO system slags were analyzed via Raman spectroscopy. The melt structure analysis results showed that there are five silicon oxygen tetrahedral structures Q⁰_Si，Q¹_Si，Q²_Si，Q³_Si and Q⁴_Si and three aluminum oxygen tetrahedral structures Q²_Al，Q³_Al and Q⁴_Al in the slag. With the increase of basicity and the decrease of Al₂O₃ mass fraction， the tetrahedral structure with high degree of polymerization changes to low degree of polymerization， the number of non bridging oxygen in the slag increases and the degree of polymerization decreases. The physical property test results showed that the viscosity increases with the increase of Al₂O₃ mass fraction and decreases with the increase of basicity. The surface tension decreases with the increase of Al₂O₃ mass fraction and increases with the increase of basicity， which is consistent with the microstructure transformation behavior of slag. The effects of slag metal interfacial reaction on the microstructure， physical properties and behavior of slag entrapment are discussed.

Key words: mold flux; ingot casting; microstructure; Raman spectrum; physical property

CLC Number:

WANG Zhen， JIANG Mao-fa， LIU Cheng-jun， MIN Yi. Microstructure Analysis of Mold Flux of Cao-SiO₂-Al₂O₃-Na₂O-MgO System for Ingot Casting[J]. Journal of Northeastern University(Natural Science), 2023, 44(4): 517-523.

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Microstructure Analysis of Mold Flux of Cao-SiO₂-Al₂O₃-Na₂O-MgO System for Ingot Casting

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