Analysis on the formation of V-shape segregation in rail steel bloom

Li Hongguang; Xu Mingli; Feng Yuanchao; Zeng Wu

doi:10.7513/j.issn.1004-7638.2023.05.027

Volume 44 Issue 5

Oct. 2023

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Li Hongguang, Xu Mingli, Feng Yuanchao, Zeng Wu. Analysis on the formation of V-shape segregation in rail steel bloom[J]. IRON STEEL VANADIUM TITANIUM, 2023, 44(5): 180-187. doi: 10.7513/j.issn.1004-7638.2023.05.027

Citation:

Li Hongguang, Xu Mingli, Feng Yuanchao, Zeng Wu. Analysis on the formation of V-shape segregation in rail steel bloom[J]. IRON STEEL VANADIUM TITANIUM, 2023, 44(5): 180-187. doi: 10.7513/j.issn.1004-7638.2023.05.027

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Analysis on the formation of V-shape segregation in rail steel bloom

doi: 10.7513/j.issn.1004-7638.2023.05.027

1.
Pangang Group Research Institute Co., Ltd., State Key Laboratory of Vanadium and Titanium Resource Comprehensive Utilization, Panzhihua 617000, Sichuan, China
2.
Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093, Yunnan, China
3.
Pangang Group Steel and Vanadium Co., Ltd., Panzhihua 617000, Sichuan, China

Received Date: 2022-01-13
Available Online: 2023-11-04
Publish Date: 2023-10-31

Abstract

Abstract

In order to improve V-shape segregation in rail steel bloom, the feature of macro-profile and microstructure were tested and theoretical shrinkage value and actual volume of V-shape was compared. The influencing factors including dynamic soft reduction processes, grade of steel and technology of micro-structure control were experimentally investigated. Result shows the V-shape segregation of rail steel bloom tends to form from two steps. The first step is ‘initial V-shape segregation formed’ where the crystal nucleus caught by solidification front of bloom fully developes into coarse connected equiaxed crystals, this results into the closed micro-regions, the molten steel in micro-regions tend to be solute rich during the solidification process. And then the second step is V-shape changed, which is formed from the microstructure subside and slip by the effect of the static pressure and the negative pressure suction due to shrinkage. Based the results the key processes has been established to improve both V-shape segregation and central segregation of rail steel bloom.
- rail steel,
- solidification structure,
- V-shape segregation,
- central segregation

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References(16)

References

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