Study on the role of CaF2 in CaO-Al2O3-based mold fluxes with different acid-base property

Shi Yi; Qi Jie; Liu Chengjun; Jiang Maofa

doi:10.7513/j.issn.1004-7638.2023.06.020

Volume 44 Issue 6

Dec. 2023

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Shi Yi, Qi Jie, Liu Chengjun, Jiang Maofa. Study on the role of CaF2 in CaO-Al2O3-based mold fluxes with different acid-base property[J]. IRON STEEL VANADIUM TITANIUM, 2023, 44(6): 139-148. doi: 10.7513/j.issn.1004-7638.2023.06.020

Citation:

Shi Yi, Qi Jie, Liu Chengjun, Jiang Maofa. Study on the role of CaF₂ in CaO-Al₂O₃-based mold fluxes with different acid-base property[J]. IRON STEEL VANADIUM TITANIUM, 2023, 44(6): 139-148. doi: 10.7513/j.issn.1004-7638.2023.06.020

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Study on the role of CaF₂ in CaO-Al₂O₃-based mold fluxes with different acid-base property

doi: 10.7513/j.issn.1004-7638.2023.06.020

Shi Yi^{1, 2
,},
Qi Jie^{1, 2
,
,},
Liu Chengjun^{1, 2},
Jiang Maofa^{1, 2}

1.
Key Laboratory of Ecological Metallurgy of Multimetallic Mineral (Ministry Education), Shenyang 110819, Liaoning, China
2.
School of Metallurgy, Northeastern University, Shenyang 110819, Liaoning, China

Received Date: 2022-12-30
Available Online: 2024-01-11
Publish Date: 2023-12-30

Abstract

Abstract

The new CaO-Al₂O₃ based mold fluxes can effectively inhibit the interfacial reaction between Al and slag components in high-aluminum steel casting. However, there were still some problems in the casting process, such as strong crystallization performance and uneven heat transfer. Fluxing agent was one of the key factors to adjust the physical and chemical properties of slag. Based on this, the effects of typical flux CaF₂ on the microstructure, viscosity and crystalline phase of CaO-Al₂O₃ based mold fluxes with different acid-base property were studied. The results show that in the near-neutral CaO-Al₂O₃-based mold flux, the crystallization phase changes from Ca₁₂Al₁₄O₃₃+Ca₃Al₂O₆ to Ca₁₂Al₁₄O₃₂F₂+LiAlO₂+CaF₂ after adding CaF₂. The precipitation of LiAlO₂ can lead to the increase of the breaking temperature by about 175 °C, and the viscosity of the high temperature section of the slag remains basically unchanged. In the alkaline CaO-Al₂O₃-based mold flux, the crystalline phase changed from Ca₃Al₂O₆+CaO to Ca₁₂Al₁₄O₃₂F₂+LiAlO₂+CaF₂ after adding CaF₂, and the premature precipitation of single CaO was effectively inhibited. The breaking temperature is reduced by about 70 °C, and the viscosity at high temperature is significantly reduced.
- continuous casting,
- high-aluminum steel,
- CaO-Al₂O₃ based mold flux,
- fluxing agent,
- viscosity,
- crystalline phase,
- melt structure

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References(34)

References

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