Influence of alkali metal oxides on the melt structure and viscosity properties of CaO-Al<sub>2</sub>O<sub>3</sub> based mold flux

ZHANG Xiaobo; TIAN Yong; LIU Chengjun

doi:10.7513/j.issn.1004-7638.2025.04.018

Volume 46 Issue 4

Aug. 2025

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ZHANG Xiaobo, TIAN Yong, LIU Chengjun. Influence of alkali metal oxides on the melt structure and viscosity properties of CaO-Al2O3 based mold flux[J]. IRON STEEL VANADIUM TITANIUM, 2025, 46(4): 135-141. doi: 10.7513/j.issn.1004-7638.2025.04.018

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ZHANG Xiaobo, TIAN Yong, LIU Chengjun. Influence of alkali metal oxides on the melt structure and viscosity properties of CaO-Al₂O₃ based mold flux[J]. IRON STEEL VANADIUM TITANIUM, 2025, 46(4): 135-141. doi: 10.7513/j.issn.1004-7638.2025.04.018

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Influence of alkali metal oxides on the melt structure and viscosity properties of CaO-Al₂O₃ based mold flux

doi: 10.7513/j.issn.1004-7638.2025.04.018

1.
State Key Laboratory of Metal Material for Marine Equipment and Application, Anshan 114009, Liaoning, China
2.
Ansteel Iron & Steel Research Institutes, Anshan 114009, Liaoning, China
3.
Ansteel Group corporation Limited, Anshan 114009, Liaoning, China
4.
Northeastern University, School of Metallurgy, Shenyang 110819, Liaoning, China

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Received Date: 2024-12-17
Available Online: 2025-08-31
Publish Date: 2025-08-31

Abstract

Abstract

Low reactivity CaO-Al₂O₃ based mold flux can significantly reduce the intensity of slag-steel reaction in the continuous casting process of high-alumina steel. But the viscosity of this kind of mold flux is larger and the crystallization performance is stronger, which is easy to produce larger slag rims at the mold meniscus and cause casting defects. In this paper, the molecular dynamics simulation method combined with viscosity test experiment was used to analyze the similarities and differences of the effects of Li₂O, Na₂O and K₂O, which are alkali metal oxides, on the melt structure and viscosity properties of CaO-Al₂O₃ based mold flux. The results show that the charge compensation of [AlO₄]⁵⁻ tetrahedra by alkali metal oxides follows the order of Li₂O<Na₂O<K₂O, and the depolymerization ability of aluminate network structure follows the order of Li₂O>Na₂O>K₂O.
- mold flux,
- aluminates,
- alkali metals,
- melt structure,
- viscosity

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References(31)

References

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