Formation and evolution of non-metallic inclusions in 20CrMnTiH gear steel during LF-RH-CC process

Wang Zhangyin; Chen Liang; Chen Xiong; Li Pingfan

doi:10.7513/j.issn.1004-7638.2024.03.021

Volume 45 Issue 3

Jul. 2024

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Wang Zhangyin, Chen Liang, Chen Xiong, Li Pingfan. Formation and evolution of non-metallic inclusions in 20CrMnTiH gear steel during LF-RH-CC process[J]. IRON STEEL VANADIUM TITANIUM, 2024, 45(3): 155-161. doi: 10.7513/j.issn.1004-7638.2024.03.021

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Wang Zhangyin, Chen Liang, Chen Xiong, Li Pingfan. Formation and evolution of non-metallic inclusions in 20CrMnTiH gear steel during LF-RH-CC process[J]. IRON STEEL VANADIUM TITANIUM, 2024, 45(3): 155-161. doi: 10.7513/j.issn.1004-7638.2024.03.021

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Formation and evolution of non-metallic inclusions in 20CrMnTiH gear steel during LF-RH-CC process

doi: 10.7513/j.issn.1004-7638.2024.03.021

1.
Panzhihua Iron and Steel Research Institute Co., Ltd., Pangang Group,Panzhihua 617000, Sichuan, China
2.
Panzhihua Steel and Vanadium Co., Ltd., Pangang Group,Panzhihua 617000, Sichuan, China

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Received Date: 2023-02-17
Publish Date: 2024-07-02

Abstract

Abstract

The formation and evolution of non-metallic inclusions in 20CrMnTiH gear steel during LF-RH-CC process were analyzed by industrial trials, and the transformation trend of non-metallic inclusions during reoxidation and cooling solidification in 20CrMnTiH gear steel was analyzed by thermodynamic calculations. During LF refining, inclusions experience evolutions from Al₂O₃ to MgO-Al₂O₃ and CaO-MgO-Al₂O₃. After calcium treatment, inclusions are modified into CaO-MgO-Al₂O₃ and CaO-Al₂O₃-CaS. After calcium treatment at the end of RH vacuum refining, inclusions are modified into CaO-Al₂O₃-CaS with high CaS contents and CaO-MgO-Al₂O₃. During continuous casting, the content of CaS in inclusions increase with the reoxidation of steel. Thermodynamic calculations reveal that when 0.000 3% to 0.000 5% [Ca] is added to the steel, MgO-Al₂O₃ would be formed in the steel. When 0.000 5% to 0.000 7% [Ca] is added to the steel, liquid calcium aluminates would be largely formed. When the content of [Ca] exceeds 0.000 7%, CaS would be formed. Moreover, liquid inclusions would be gradually transformed into solid inclusions with the reoxidation of steel. With the decrease of temperature, the contents of CaO and CaS in inclusions decrease and the contents of MgO and Al₂O₃ in inclusions increase, leading to the formation of CaS-CaO-MgO-Al₂O₃ with high CaS contents eventually.
- 20CrMnTiH,
- inclusions,
- calcium treatment,
- reoxidation

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References(23)

References

[1]	Fuchs D, Tobie T, Stahl K. Challenges in determination of microscopic degree of cleanliness in ultra-clean gear steels[J]. Journal of Iron and Steel Research International, 2022,29(10):1583−1600. doi: 10.1007/s42243-021-00730-y
[2]	Juan R, Wang M, Li L, et al. Relationship between inclusions and internal defect spatial distribution in large forging piece for wind power generation gear[J]. ISIJ International, 2022,62(1):133−141. doi: 10.2355/isijinternational.ISIJINT-2021-356
[3]	Liu R, Sun D, Hou J, et al. Fatigue life analysis of wind turbine gear with oxide inclusion[J]. Fatigue Fracture of Engineering Materials Structures, 2021,44(3):776−787. doi: 10.1111/ffe.13393
[4]	Ji Sha, Zhang Lifeng, Luo Yan, et al. Effect of calcium treatment on nonmetallic inclusions in 20CrMnTiH gear steel[J]. Chinese Journal of Engineering, 2021,43(6):825−834. (季莎, 张立峰, 罗艳, 等. 钙处理对20CrMnTiH齿轮钢中非金属夹杂物的影响[J]. 工程科学学报, 2021,43(6):825−834. Ji Sha, Zhang Lifeng, Luo Yan, et al. Effect of calcium treatment on nonmetallic inclusions in 20 CrMnTiH gear steel [J]. Chinese Journal of Engineering, 2021, 43(6): 825-834.
[5]	Wang Kunpeng, Wang Ying, Xu Jianfei, et al. Investigation on evolution of inclusions in bearing steel during secondary refining[J]. Iron and Steel, 2022,57(6):42−49. (王昆鹏, 王郢, 徐建飞, 等. 轴承钢二次精炼过程夹杂物演变规律[J]. 钢铁, 2022,57(6):42−49. doi: 10.13228/j.boyuan.issn0449-749x.20210660 Wang Kunpeng, Wang Ying, Xu Jianfei, et al. Investigation on evolution of inclusions in bearing steel during secondary refining [J]. Iron and Steel, 2022, 57 (6): 42-49. doi: 10.13228/j.boyuan.issn0449-749x.20210660
[6]	Yang Guang, Yang Wen, Zhang Lifeng. Calcium treatment modification and influencing factors of inclusions in aluminum-killed steel[J]. Iron and Steel, 2022,57(12):66−78. (杨光, 杨文, 张立峰. 铝镇静钢中夹杂物钙处理改性及其影响因素[J]. 钢铁, 2022,57(12):66−78. doi: 10.13228/j.boyuan.issn0449-749x.20220313 Yang Guang, Yang Wen, Zhang Lifeng. Calcium treatment modification and influencing factors of inclusions in aluminum-killed steel [J]. Iron and Steel, 2022, 57(12): 66-78. doi: 10.13228/j.boyuan.issn0449-749x.20220313
[7]	Dieter Janke Z M, Peter V, Heinen A. Improvement of castability and quality of continuously cast steel[J]. ISIJ International, 2000,40(1):31−39. doi: 10.2355/isijinternational.40.31
[8]	Gollapalli V, Raomb V, Karmached P S, et al. Modification of oxide inclusions in calcium-treated Al-killed high sulphur steels[J]. Ironmaking & Steelmaking, 2019,46(7):663−670.
[9]	Pretorius E B, Oltman H G, Cash T. The effective modification of spinel inclusions by Ca treatment in LCAK steel[J]. Iron & Steel Technology, 2011,7(7):31−44.
[10]	Xu J, Huang F, Wang X. Formation mechanism of CaS-Al₂O₃ inclusions in low sulfur Al-killed steel after calcium treatment[J]. Metall. Mater. Trans. B, 2016,47(2):1217−1227. doi: 10.1007/s11663-016-0599-8
[11]	Choudhary S K, Ghosh A. Thermodynamic evaluation of formation of oxide–sulfide duplex inclusions in steel[J]. ISIJ International, 2008,48(11):1552−1559. doi: 10.2355/isijinternational.48.1552
[12]	Verma N, Pistorius P C, Fruehan R J, et al. Calcium modification of spinel inclusions in aluminum-killed steel: Reaction steps[J]. Metall. Mater. Trans. B, 2012,43(4):830−840. doi: 10.1007/s11663-012-9660-4
[13]	Xie Y, Meng X, Deng X, et al. Evolution of sulphide inclusion in Mg–Ca treating gear steel [J]. Ironmaking & Steelmaking, 2022: 1−7.
[14]	Xu G, Jiang Z, Li Y. Formation mechanism of CaS-bearing inclusions and the rolling deformation in Al-killed, low-alloy steel with Ca treatment[J]. Metall. Mater. Trans. B, 2016,47(4):2411−2420. doi: 10.1007/s11663-016-0695-9
[15]	Zhao D, Li H, Bao C, et al. Inclusion evolution during modification of alumina inclusions by calcium in liquid steel and deformation during hot rolling process[J]. ISIJ International, 2015,55(10):2115−2124. doi: 10.2355/isijinternational.ISIJINT-2015-064
[16]	Bielefeldt W V, Vilela A C F. Computational thermodynamic study of inclusions formation in the continuous casting of SAE 8620 steel[J]. Steel Research International, 2010,81(12):1064−1069. doi: 10.1002/srin.201000057
[17]	Ahmad H, Zhao B, Sha L, et al. Formation of complex inclusions in gear steels for modification of manganese sulphide[J]. Metals, 2021,11(12):2051−2064. doi: 10.3390/met11122051
[18]	Ren Y, Zhang L, Ling H, et al. A reaction model for prediction of inclusion evolution during reoxidation of Ca-treated Al-killed steels in tundish[J]. Metall. Mater. Trans. B, 2017,48(3):1−6.
[19]	Gao Shengya, Jiang Min, Hou Zewang, et al. Effect of calciumtreatment on non-metallic inclusions in high carbon aluminum killed steel(Article)[J]. Iron and Steel, 2017,52(4):25−30. (高胜亚, 姜敏, 侯泽旺, 等. 钙处理对高碳铝镇静钢中夹杂物的影响[J]. 钢铁, 2017,52(4):25−30. doi: 10.13228/j.boyuan.issn0449-749x.20160311 Gao Shengya, Jiang Min, Hou Zewang, et al. Effect of calciumtreatment on non-metallic inclusions in high carbon aluminum killed steel(Article) [J]. Iron and Steel, 2017, 52(4): 25-30. doi: 10.13228/j.boyuan.issn0449-749x.20160311
[20]	Yang G, Wang X, Huang F, et al. Influence of calcium addition on inclusions in LCAK steel with ultralow sulfur content[J]. Metall. Mater. Trans. B, 2014,46(1):145−154.
[21]	Hou Z, Jiang M, Yang E, et al. Inclusion characterization in aluminum-deoxidized special steel with certain sulfur content under combined influences of slag refining, calcium treatment, and reoxidation[J]. ISIJ International, 2018,49(6):3056−3066.
[22]	Kim T S, Chung Y, Holappa L, et al. Effect of rice husk ash insulation powder on the reoxidation behavior of molten steel in continuous casting tundish[J]. Metall. Mater. Trans. B, 2017,48(3):1736−1747. doi: 10.1007/s11663-017-0971-3
[23]	Shi C, Zheng D, Guo B, et al. Evolution of oxide-sulfide complex inclusions and its correlation with steel cleanliness during electroslag rapid remelting (ESRR) of tool steel[J]. Metall. Mater. Trans. B, 2018,49(6):3390−3402. doi: 10.1007/s11663-018-1398-1