Revolution and control of Fe-Al-Ti-O complex oxide inclusions in ultralow-carbon steel during refining process

GU Chao; ZHAO Li-hua; GAN Peng

doi:10.13374/j.issn2095-9389.2019.06.007

Volume 41 Issue 6

Jun. 2019

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Article Navigation > Chinese Journal of Engineering > 2019 > 41(6): 757-762

GU Chao, ZHAO Li-hua, GAN Peng. Revolution and control of Fe-Al-Ti-O complex oxide inclusions in ultralow-carbon steel during refining process[J]. Chinese Journal of Engineering, 2019, 41(6): 757-762. doi: 10.13374/j.issn2095-9389.2019.06.007

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GU Chao, ZHAO Li-hua, GAN Peng. Revolution and control of Fe-Al-Ti-O complex oxide inclusions in ultralow-carbon steel during refining process[J]. Chinese Journal of Engineering, 2019, 41(6): 757-762. doi: 10.13374/j.issn2095-9389.2019.06.007

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Revolution and control of Fe-Al-Ti-O complex oxide inclusions in ultralow-carbon steel during refining process

doi: 10.13374/j.issn2095-9389.2019.06.007

GU Chao¹,
ZHAO Li-hua^{2
,
,},
GAN Peng¹

1.
State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, Beijing 100083, China
2.
School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China

More Information

Corresponding author: ZHAO Li-hua, E-mail: 15210951549@sina.cn
Received Date: 2018-12-20
Publish Date: 2019-06-01

Abstract

Abstract

Ultralow-carbon steel is an important material for automobile production. Titanium is usually added in this steel grade to form a precipitant and improve the deep drawing property of the steel. However, due to the deoxidation capacity of Ti, Ti addition will directly generate Ti-bearing oxide inclusions instead of the precipitant. To reduce the amount of Ti-bearing oxide inclusions, samples were collected during the RH refining based on the basic oxygen furnace-Ruhrstahl-Heraeus reactor-continuous casting (BOF-RH-CC) ultralow-carbon steel production process, and the oxygen content and inclusion characterization after Al addition and Ti addition were analyzed. The thermodynamics calculation software FactSage was adopted to calculate the Fe-Al-Ti-O inclusion stability phase diagram. The results show that the Al₂O₃ inclusion usually acts as the nucleation point of the Ti-bearing oxide inclusion, which wraps the Al₂O₃ inclusion to form the Al-Ti-O complex inclusion. To avoid the generation of the Ti-bearing oxide inclusions, the mass fraction of dissolved Al in the molten steel should be greater than 0.01% when the Ti mass fraction is 0.1%. Furthermore, the generation and growth behavior of the Ti-bearing oxide inclusion were also studied. Based on the calculation of the growth rate and the comparison of the adhesion work of the Al₂O₃ inclusion and the Ti₂O₃ inclusion, it is concluded that the growth rate of Ti₂O₃ inclusion is greater than that of Al₂O₃ inclusion, and it is more difficult for Ti₂O₃ inclusions to collide with each other and to be removed at 1600℃. Therefore, the generation of Ti-bearing oxide inclusions should be strictly controlled to improve the removal rate of oxide inclusions in ultralow-carbon steels.
- ultralow-carbon steel,
- RH refining,
- Al₂O₃ inclusion,
- Ti₂O₃ inclusion

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References(17)

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