Skip to main content
Log in

Improving cleanliness of 30Cr2Ni4MoV low-pressure rotor steel by CaO–SiO2–MgO–Al2O3 slag refining

  • Original Paper
  • Published:
Journal of Iron and Steel Research International Aims and scope Submit manuscript

Abstract

The optimal composition of a CaO–SiO2–Al2O3–MgO slag in the ladle furnace refining process was investigated to precisely control the contents of [O] and [Si] and improve the cleanliness of 30Cr2Ni4MoV steel. The iso-[O] lines and iso-[Si] lines of the equilibrium between the CaO–SiO2–Al2O3–MgO refining slag and 30Cr2Ni4MoV steel at 1873 K were calculated by the thermodynamic software FactSage 7.3, and the activities of SiO2, Al2O3 and CaO in the refining slag were discussed to achieve the optimal composition range of the refining slag. Finally, combined with high-temperature “slag–steel” equilibrium experiments, the effects of different refining slags on the oxygen contents, chemical compositions, quantities and sizes of inclusions in steels were studied, and then the thermodynamic formation mechanism of MgAl2O4 inclusions in 30Cr2Ni4MoV steel was discussed. The results showed that the contents of dissolved [O] and [Si] in steel can be controlled below 10 × 10–6 and 0.05%, respectively; when the slag basicity is above 7, the CaO/Al2O3 ratio is above 1, and the mass fraction of SiO2 in the slag does not exceed 7%. The chemical composition of the slag has a great influence on the removal and composition of inclusions. The assessed stability phase diagrams of MgO, Al2O3 and MgO·Al2O3 inclusion formation in the Fe–Al–Mg–O system calculated by FactSage 7.3 show good agreement with the experimental results.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10
Fig. 11
Fig. 12
Fig. 13

Similar content being viewed by others

References

  1. M. Zhang, J.H. Zeng, P. Hong, J. Iron Steel Res. Int. 18 (2011) No. S2, 195–200.

    Google Scholar 

  2. H.Y. Yu, X.H. Wang, J. Zhang, W.J. Wang, J. Iron Steel Res. Int. 22 (2015) 573–581.

    Article  Google Scholar 

  3. W. Long, F. Pei, Y. Chen, S.Q. Li, J. Iron Steel Res. Int. 19 (2012) No. 4, 17–21.

    Article  Google Scholar 

  4. Z.Y. Deng, M.Y. Zhu, B.J. Zhong, Y.G. Dai, J. Iron Steel Res. Int. 20 (2013) No. 2, 21–26.

    Article  Google Scholar 

  5. H.Y. Tang, Y. Wang, G.H. Wu, L. Peng, J.Q. Zhang, J. Iron Steel Res. Int. 24 (2017) 879–887.

    Article  Google Scholar 

  6. F.Z. Xuan, X.Q. Huang, S.T. Tu, Mater. Des. 29 (2008) 1533–1539.

    Article  Google Scholar 

  7. Y.P. Wang, C.J. Han, C. Wang, S.K. Li, Mater. Sci. 46 (2011) 2922–2927.

    Article  Google Scholar 

  8. C. Fei, Z.S. Cui, S.J. Cheng, Mater. Sci. Eng. A 528 (2011) 5073–5080.

    Article  Google Scholar 

  9. F. Chen, F.C. Ren, Z.S. Cui, X.M. Lai, J. Iron Steel Res. Int. 21 (2014) 521–526.

    Article  Google Scholar 

  10. W.L. Zhao, D.P. Wang, H.D. Wang, S.C. Ma, Y.Y. Wang, Y.Q. Zhang, Mater. Trans. 59 (2018) 822–828.

    Article  Google Scholar 

  11. A. Ghosh, Secondary Steelmaking: Principles and Applications, CRC Press LCC, Washington D.C., USA, 2000.

    Book  Google Scholar 

  12. J. Maciejewski, J. Fail. Anal. Preven. 15 (2015) 169–178.

    Article  Google Scholar 

  13. W.J. Ma, Y.P. Bao, M. Wang, D.W. Zhao, Ironmak. Steelmak. 41 (2014) 26–30.

    Article  Google Scholar 

  14. W.L. Dong, H.W. Ni, H. Zhang, Z.A. Lv, Int. J. Min. Met. Mater. 23 (2016) 269–275.

    Article  Google Scholar 

  15. R. Inoue, H. Suito, ISIJ Int. 36 (1996) 528–536.

    Article  Google Scholar 

  16. M. Hino, K. Ito, Thermodynamic Data for Steelmaking, Tohoku University Press, Tokyo, Japan, 2010.

    Google Scholar 

  17. X.K. Huang, Principles of Iron and Steel Metallurgy, Metallurgical Industry Press, Beijing, China, 2013.

    Google Scholar 

  18. E.E. Underwood, Quantitative Stereology for Microstructural Analysis, Springer, Plenum Press, New York, USA, 1973.

    Book  Google Scholar 

  19. C.S. Liu, D. Kumar, B.A. Webler, P.C. Pistorius, Metall. Mater. Trans. B 51 (2020) 529–542.

    Article  Google Scholar 

  20. N. Eustathopoulos, M.G. Nicholas, B. Drevet, Wettability at High Temperatures, Elsevier, Oxford, UK, 1999.

    Google Scholar 

  21. K.C. Mills, S. Sridhar, Ironmak. Steelmak. 26 (1999) 262–268.

    Article  Google Scholar 

  22. H. Abdeyazdan, N. Dogan, M.A. Rhamdhani, M.W. Chapman, B.J. Monaghan, Metall. Mater. Trans. B 46 (2015) 208–219.

    Article  Google Scholar 

  23. T. Nishi, K. Shimme, Tetsu-to-Hagané 84 (1998) 837.

    Article  Google Scholar 

  24. G. Okuyama, K. Yamaguchi, S. Takeuchi, K. Sorimachi, ISIJ Int. 40 (2000) 121–128.

    Article  Google Scholar 

  25. H. Todoroki, K. Mizuno, ISIJ Int. 44 (2004) 1350–1357.

    Article  Google Scholar 

  26. H. Ushiyama, G. Yuasa, T. Yajima, Ironmak. Steelmak. 5 (1978) 121–134.

    Google Scholar 

  27. L.Z. Wang, S.F. Yang, J.S. Li, T. Wu, W. Liu, J.Z. Xiong, Metall. Mater. Trans. B 47 (2016) 99–107.

    Article  Google Scholar 

  28. J.H. Park, S.K. Dong, Metall. Mater. Trans. B 36 (2005) 495–502.

    Article  Google Scholar 

  29. H. Ohta, H. Suito, Metall. Mater. Trans. B 29 (1998) 119–129.

    Article  Google Scholar 

Download references

Acknowledgements

The current study was also supported by the National Natural Science Foundation of China (Grant Nos. 51774217, 52074198 and 51604201).

Author information

Authors and Affiliations

Authors

Corresponding authors

Correspondence to Cheng-song Liu or Hua Zhang.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Peng, Yb., Liu, Cs., Yang, L. et al. Improving cleanliness of 30Cr2Ni4MoV low-pressure rotor steel by CaO–SiO2–MgO–Al2O3 slag refining. J. Iron Steel Res. Int. 29, 1434–1445 (2022). https://doi.org/10.1007/s42243-022-00757-9

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s42243-022-00757-9

Keywords

Navigation