Novel mechanism for the modification of Al<sub>2</sub>O<sub>3</sub>-based inclusions in ultra-low carbon Al-killed steel considering the effects of magnesium and calcium

Jing Guo; Shu-sen Cheng; Han-jie Guo; Ya-guang Mei

doi:10.1007/s12613-018-1571-1

Volume 25 Issue 3

Mar. 2018

Turn off MathJax

Article Contents

Article Navigation > International Journal of Minerals, Metallurgy and Materials > 2018 > 25(3): 280-287

Jing Guo, Shu-sen Cheng, Han-jie Guo, and Ya-guang Mei, Novel mechanism for the modification of Al₂O₃-based inclusions in ultra-low carbon Al-killed steel considering the effects of magnesium and calcium, Int. J. Miner. Metall. Mater., 25(2018), No. 3, pp. 280-287. https://doi.org/10.1007/s12613-018-1571-1

Cite this article as:

Jing Guo, Shu-sen Cheng, Han-jie Guo, and Ya-guang Mei, Novel mechanism for the modification of Al2O3-based inclusions in ultra-low carbon Al-killed steel considering the effects of magnesium and calcium, Int. J. Miner. Metall. Mater., 25(2018), No. 3, pp. 280-287. https://doi.org/10.1007/s12613-018-1571-1

Citation:

PDF( 3479 KB)

Research Article

Novel mechanism for the modification of Al₂O₃-based inclusions in ultra-low carbon Al-killed steel considering the effects of magnesium and calcium

+ Author Affiliations

Corresponding author:
Jing Guo E-mail: guojing@ustb.edu.cn
Received: 7 June 2017; Revised: 18 September 2017; Accepted: 21 September 2017

Abstract

Abstract

Many researchers have explored the inclusion modification mechanism to improve non-metallic inclusion modifications in steelmaking. In this study, two types of industrial trials on inclusion modifications in liquid steel were conducted using ultra-low-carbon Al-killed steel with different Mg and Ca contents to verify the effects of Ca and Mg contents on the modification mechanism of Al₂O₃-based inclusions during secondary refining. The results showed that Al₂O₃-based inclusions can be modified into liquid calcium aluminate or a multi-component inclusion with the addition of a suitable amount of Ca. In addition,[Mg] in liquid steel can further reduce CaO in liquid calcium aluminate to drive its evolution into CaO-MgO-Al₂O₃ multi-component inclusions. Thermodynamic analysis confirmed that the reaction between[Mg] and CaO in liquid calcium aluminate occurs when the MgO content of liquid calcium aluminate is less than 3wt% and the temperature is higher than 1843 K.
- inclusions;
- mechanism;
- modification;
- ultra-low carbon Al-killed steel;
- calcium treatment;
- magnesium content

FullText(HTML)

Supplements(0)

References(20)

References

[1]	G. Ye, P. Jönsson, and T. Lund, Thermodynamics and kinetics of the modification of Al₂O₃ inclusions, ISIJ Int., 36(1996), Suppl., p. S105.
[2]	Z.Y. Deng and M.Y. Zhu, A new double calcium treatment method for clean steel refining, Steel Res. Int., 84(2013), No. 6, p. 519.
[3]	M. Jiang, X.H. Wang, B. Cheng, and W.J. Wang, Laboratory study on evolution mechanisms of non-metallic inclusions in high strength alloyed steel refined by high basicity slag, ISIJ Int., 50(2010), No. 1, p. 95.
[4]	S.F. Yang, Q.Q. Wang, L.F. Zhang, J.S. Li, and K. Peaslee, Formation and modification of MgO·Al₂O₃-based inclusions in alloy steels, Metall. Mater. Trans. B, 43(2012), No. 4, p. 731.
[5]	Z.Y. Deng and M.Y. Zhu, Evolution mechanism of non-metallic inclusions in Al-killed alloyed steel during secondary refining process, ISIJ Int., 53(2013), No. 3, p. 450.
[6]	J. Guo, S.S. Cheng, Z.J. Cheng, and L. Xin, Thermodynamics for precipitation of CaS bearing inclusion and their deformation during rolling process for Al-killed Ca-treated steel, Steel Res. Int., 84(2013), No. 6, p. 545.
[7]	J. Guo, S.S. Cheng, and Z.J. Cheng, Mechanism of non-metallic inclusion formation and modification and their deformation during CSP process for aluminum-killed steel, ISIJ Int., 53(2013), No. 12, p. 2142.
[8]	T.S. Zhang, Y. Min, C.J. Liu, and M.F. Jiang, Effect of Mg addition on the evolution of inclusions in Al-Ca deoxidized melts, ISIJ Int., 55(2015), No. 8, p. 1541.
[9]	W.J. Ma, Y.P. Bao, M. Wang, and L.H. Zhao. Effect of Mg and Ca treatment on behavior and particle size of inclusions in bearing steels, ISIJ Int., 54(2014), No. 3, p. 536.
[10]	A. Martín, E. Brandaleze, J. Madías, R. Donayo, A. Gómez, and J. Pérez, Study about downgrading variables by inclusionary cleanliness in the laddle furnace at Ternium Siderar,[in] Proceedings of the 7th International Conference of Clean Steel, Balatonfüred, Hungary, 2007, p. 203.
[11]	N. Dogan, R.J. Longbottom, M.H. Reid, M.W. Chapman, P. Wilson, L. Moore, and B.J. Monaghan, Morphology and composition changes of spinel (MgAl₂O₄) inclusions in steel, Ironmaking Steelmaking, 42(2015), No. 3, p. 185.
[12]	W.G. Seo, W.H. Han, J.S. Kim, and J.J. Park, Deoxidation equilibria among Mg, Al and O in liquid iron in the presence of MgO Al₂O₃ spinel, ISIJ Int., 43(2003), No. 2, p. 201.
[13]	J.W. Kim, S.K. Kim, D.S. Kim, Y.D. Lee, and P.K. Yang, Formation mechanism of Ca-Si-Al-Mg-Ti-O inclusions in type 304 stainless steel, ISIJ Int., 36(1996), Suppl., p. S140.
[14]	W.Y. Cha, D.S. Kim, Y.D. Lee, and J.J. Park, A thermodynamic study on the inclusions formation in ferritic stainless steel melt, ISIJ Int., 44(2004), No. 7, p. 1134.
[15]	J.H. Park, Formation mechanism of spinel-type inclusions in high-alloyed stainless steel melts, Metall. Mater. Trans. B, 38(2007), No. 4, p. 657.
[16]	Y. Ehara, S. Yokoyama, and M. Kawakami, Formation mechanism of inclusions containing MgO·Al₂O₃ spinet in type 304 stainless steel, Tetsu-to-Hagane, 93(2007), No. 3, p. 208.
[17]	Y. Ehara, S. Yokoyama, and M. Kawakami, Control of formation of spinel inclusion in type 304 stainless steel by slag composition, Tetsu-to-Hagane, 93(2007), No. 7, p. 475.
[18]	H. Suito and R. Inoue, Thermodynamics on control of inclusions composition in ultra-clean steels, ISIJ Int., 36(1996), No. 5, p. 528.
[19]	J.W. Nybakken, Steelmaking Data Sourcebook, Edited by the Japan Society for the Promotion of Science, Gordon & Breach Science Publishers, New York, 1987, p. 142.
[20]	J. Guo, S.S. Cheng, and Z.J. Cheng, Characteristics of deoxidation and desulfurization during LF refining Al-killed steel by highly basic and low oxidizing slag, J. Iron. Steel Res. Int., 21(2014), No. 2, p. 166.