Research on the evolution of inclusions in 20CrMnTi gear steel and the improvement of steel liquid cleanliness

LI Haitao; GAO Fang; LI Haozhe; LI Likai; ZHANG Xiaohua; GU Chao; BAO Yanping

doi:10.7513/j.issn.1004-7638.2025.03.018

Volume 46 Issue 3

Jun. 2025

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Article Navigation > IRON STEEL VANADIUM TITANIUM > 2025 > 46(3): 122-131

LI Haitao, GAO Fang, LI Haozhe, LI Likai, ZHANG Xiaohua, GU Chao, BAO Yanping. Research on the evolution of inclusions in 20CrMnTi gear steel and the improvement of steel liquid cleanliness[J]. IRON STEEL VANADIUM TITANIUM, 2025, 46(3): 122-131. doi: 10.7513/j.issn.1004-7638.2025.03.018

Citation:

LI Haitao, GAO Fang, LI Haozhe, LI Likai, ZHANG Xiaohua, GU Chao, BAO Yanping. Research on the evolution of inclusions in 20CrMnTi gear steel and the improvement of steel liquid cleanliness[J]. IRON STEEL VANADIUM TITANIUM, 2025, 46(3): 122-131. doi: 10.7513/j.issn.1004-7638.2025.03.018

Citation:

LI Haitao, GAO Fang, LI Haozhe, LI Likai, ZHANG Xiaohua, GU Chao, BAO Yanping. Research on the evolution of inclusions in 20CrMnTi gear steel and the improvement of steel liquid cleanliness[J]. IRON STEEL VANADIUM TITANIUM, 2025, 46(3): 122-131. doi: 10.7513/j.issn.1004-7638.2025.03.018

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Research on the evolution of inclusions in 20CrMnTi gear steel and the improvement of steel liquid cleanliness

doi: 10.7513/j.issn.1004-7638.2025.03.018

1.
Eastran Special Steel Co., Ltd., Changzhou 213000, Jiangsu, China
2.
State key Lab of Advanced Metallurgy, University of Science and Technology Beijing, Beijing 100083, China

Received Date: 2024-10-09
Publish Date: 2025-06-30

Abstract

Abstract

In this work, taking a domestic factory’s 20CrMnTi gear steel as the research object, the limiting factors for improving the cleanliness of the steel liquid were analyzed through systematic sampling, and two optimization measures were proposed. Firstly, based on FactSage7.2, the effects of refining slag basicity and calcium aluminum ratio on CaO and Al₂O₃ activity were calculated. Taking into account the low-temperature liquid phase region of the slag system, the target refining slag system range was determined as follows: R=4-6, w (SiO₂)=9%-13.5%, w (Al₂O₃)=22.5%-31.5%, and w (Fe₂O₃+MnO)<1%. Then, based on the current situation of excessive Ca-treatment, a thermodynamic database had been utilized to construct an accurate calculation model for Ca-treatment. Finally, the results of industrial experiments showed that with the optimization of the refining slag and the reduction of Ca-treatment, the number of inclusions in the smelting process significantly reduced, and the number of inclusions in the casting billet decreased by 56.3% compared to the original process.
- 20CrMnTi,
- gear steel,
- improvement of cleanliness,
- optimization of slag system,
- Ca-treatment

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References(29)

References

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