Subsurface hooks in continuous casting slabs of low-carbon steel

ZHANG Xu-bin; ZHANG Li-feng; WANG Hao; WANG Sheng-dong; WANG Qiang-qiang; YANG Wen

doi:10.13374/j.issn2095-9389.2017.02.013

Volume 39 Issue 2

Feb. 2017

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Article Navigation > Chinese Journal of Engineering > 2017 > 39(2): 251-258

ZHANG Xu-bin, ZHANG Li-feng, WANG Hao, WANG Sheng-dong, WANG Qiang-qiang, YANG Wen. Subsurface hooks in continuous casting slabs of low-carbon steel[J]. Chinese Journal of Engineering, 2017, 39(2): 251-258. doi: 10.13374/j.issn2095-9389.2017.02.013

Citation:

ZHANG Xu-bin, ZHANG Li-feng, WANG Hao, WANG Sheng-dong, WANG Qiang-qiang, YANG Wen. Subsurface hooks in continuous casting slabs of low-carbon steel[J]. Chinese Journal of Engineering, 2017, 39(2): 251-258. doi: 10.13374/j.issn2095-9389.2017.02.013

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Subsurface hooks in continuous casting slabs of low-carbon steel

doi: 10.13374/j.issn2095-9389.2017.02.013

1) School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China
2) Steelmaking Department, Shougang Jingtang United Iron & Steel Co., Ltd., Tangshan 063200, China

Received Date: 2016-04-20

Abstract

Abstract

Hook characteristics in continuous casting slabs of low-carbon steel under different casting conditions were investigated. According to hook morphology, hooks were classified into different types. Distributions of bubbles and inclusions near hooks were analyzed, and the influence of casting parameters on hook depth was discussed. Bikerman's equations and theory of meniscus solidification were used to explain the various hook morphology. Results show that on the basis of morphology hooks can be classified into four types, including whole-leaf type, double-hook type, truncated type and re-solidified type. The percentage of re-solidified type is the highest (46.8%), and the percentages of whole-leaf type, truncated type and double-hook type are respectively 25.3%, 7.6% and 6.3%. Studies demonstrate that the inclusion number near hooks is obviously higher than that in other zone, indicating floating inclusions in the mold can be captured by hooks. Comparing different casting parameters, the use of FC-Mold, the decrease of the submerged depth of the submerged entry nozzle (SEN) and the increase of casting speed can reduce the hook depth. Calculated results of Bikerman's equation and theory of meniscus solidification can explain the formation mechanisms of different hook morphologies.
- low-carbon steel,
- continuous casting,
- slabs,
- oscillation marks,
- solidified hooks

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References(19)

References

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