Metallurgical and Materials Transactions B

, Volume 50, Issue 6, pp 2867–2883 | Cite as

Closure of Internal Porosity in Continuous Casting Bloom During Heavy Reduction Process

  • Chenhui Wu
  • Cheng JiEmail author
  • Miaoyong Zhu


To investigate the closure behavior of internal porosity (also referred to as internal void) in continuous casting bloom during heavy reduction (HR) and thus provide theoretical guidance for minimizing this kind of internal defect more effectively with HR, a three-dimensional (3D) mechanical model was developed based on the predicted temperature field by a 2D heat transfer model. With this 3D mechanical model, closure behaviors of internal porosity in continuous casting bloom during HR at and after the strand solidification end under different process conditions were numerically studied. It was found that the void axis length decreased significantly along the bloom thickness direction and increased slightly along the casting and bloom width directions after HR, and the influence of the initial void size on the void closure was not obvious. With a decrease of temperature difference between the bloom surface and center, HR efficiency for minimizing internal void decreased, while the required reduction force significantly increased. Compared with blooms with a uniform temperature distribution of 1100 °C, the void closure index after HR implemented at the strand solidification end was increased by ~ 25 pct. Compared with a conventional flat roll, the application of a convex roll during HR could contribute to minimizing the internal porosity more effectively and significantly enhance the reduction capacity of the withdrawal and straightening units. The void closure index of ηs and ηv (where ηs and ηv were defined based on the variation of the void aspect ratio and the void volume, respectively) was closely related to the equivalent strain (εeq) and the hydrostatic integration parameter (Q), respectively, and two mathematical equations were derived to quantitatively describe the relationship of ηs − εeq and ηv − Q.



The present work is financially supported by the National Natural Science Foundation of China No. 51974078 and U1560208, the Fundamental Research Funds for the Central Universities of China N172504024 and N182515006. Special thanks are due to our cooperating company for industrial trials and applications.


  1. 1.
    H. Kakimoto, T. Arikawa, Y. Takahashi, T. Tanaka and Y. Imaida: J. Mater. Process. Technol., 2010, vol. 210, pp. 415–22.CrossRefGoogle Scholar
  2. 2.
    Y.S. Lee, S.U. Lee, C.J. Van Tyne and B.D. Joo: J. Mater. Process. Technol., 2011, vol. 211, pp. 1136-45.CrossRefGoogle Scholar
  3. 3.
    J.J. Park: ISIJ Int., 2013, vol. 53, pp. 1420-6.CrossRefGoogle Scholar
  4. 4.
    M.S. Chen and Y.C. Lin: Int. J. Plast., 2013, vol. 49, pp. 53-70.CrossRefGoogle Scholar
  5. 5.
    D.C. Chen: J. Mater. Process. Technol., 2006, vol. 180, pp. 193-200.CrossRefGoogle Scholar
  6. 6.
    M. Nakasaki, I. Takasu and H. Utsunomiya: J. Mater. Process. Technol., 2006, vol. 177, pp. 521-4.CrossRefGoogle Scholar
  7. 7.
    J. Chen, K. Chandrashekhara, C. Mahimkar, S.N. Lekakh and V.L. Richards: J. Mater. Process. Technol., 2011, vol. 211, pp. 245-55.CrossRefGoogle Scholar
  8. 8.
    G.S. Li, W. Yu and Q.W. Cai: Metall. Mater. Trans. B, 2015, vol. 46, pp. 831-40.Google Scholar
  9. 9.
    G.S. Li, W. Yu and Q. Cai: J. Mater. Process. Technol., 2016, vol. 227, pp. 41-8.CrossRefGoogle Scholar
  10. 10.
    J.J. Park: Metall. Mater. Trans. A, 2016, vol. 47, pp. 479-87.CrossRefGoogle Scholar
  11. 11.
    X.K. Zhao, J.M. Zhang, S.W. Lei and Y.N. Wang: Steel Res. Int., 2014, vol. 85, pp. 1533-43.CrossRefGoogle Scholar
  12. 12.
    Z.G. Xu, X.H. Wang and M. Jiang: Steel Res. Int., 2017, vol. 88, pp. 231-42.Google Scholar
  13. 13.
    Q.P. Dong, J.M. Zhang, B. Wang and X.K. Zhao: J. Mater. Process. Technol., 2016, vol. 238, pp. 81-8.CrossRefGoogle Scholar
  14. 14.
    J.P. Zhao, L. Liu, W.W. Wang and H. Lu: Ironmaking Steelmaking, 2017, Scholar
  15. 15.
    C. Ji, C.H. Wu and M.Y. Zhu: JOM, 2016, vol. 68, pp. 3107-15.CrossRefGoogle Scholar
  16. 16.
    C. Ji, G.L. Li, C.H. Wu and M.Y. Zhu: Metall. Mater. Trans. B, 2019, vol. 50, pp. 110-22.CrossRefGoogle Scholar
  17. 17.
    C.H. Wu, C. Ji and M.Y. Zhu: J. Mater. Process. Technol., 2019, vol. 271, pp. 651-9.CrossRefGoogle Scholar
  18. 18.
    K. Miyazawa and K. Schwerdtfeger: rch. Eisenhuettenwes., 1981, vol. 52, pp. 415–22.Google Scholar
  19. 19.
    T. Kajitani, J.-M. Drezet, and M. Rappaz: Metall. Mater. Trans. A, 2001, vol. 32A, pp. 1479-91.CrossRefGoogle Scholar
  20. 20.
    M. Wu, J. Domitner, and A. Ludwig: Metall. Mater. Trans. A, 2012, vol. 43A, pp. 945-64.CrossRefGoogle Scholar
  21. 21.
    J. Domitner, M. Wu, A. Kharicha, A. Ludwig, B. Kaufmann, J. Reiter, and T. Schaden: Metall. Mater. Trans. A, 2013, vol. 45, pp. 1415-34.Google Scholar
  22. 22.
    M. Wu, and A. Ludwig: Metall. Mater. Trans. A, 2006, vol. 37, pp. 1613–31.CrossRefGoogle Scholar
  23. 23.
    R. Guan, C. Ji, M.Y. Zhu, and S.M. Deng, Metall. Mater. Trans. B, 2018, vol. 49, pp. 2571–83.CrossRefGoogle Scholar
  24. 24.
    R. Guan, C. Ji, C. H. Wu, and M. Y. Zhu, Int. J. Heat Mass Transfer, 2019, vol. 141, pp. 503-16.CrossRefGoogle Scholar
  25. 25.
    H.M. Wang, G.R. Li, Y.C. Lei, Y.T. Zhao, Q.X. Dai and J.J. Wang: ISIJ Int., 2005, vol. 45, pp. 1291-6.CrossRefGoogle Scholar
  26. 26.
    C. Ji, S. Luo and M.Y. Zhu: ISIJ Int., 2014, vol. 54, pp. 504-10.CrossRefGoogle Scholar
  27. 27.
    C. Ji, Z.L. Wang, C.H. Wu and M.Y. Zhu: Metall. Mater. Trans. B, 2018, vol. 49, pp. 767-82.CrossRefGoogle Scholar
  28. 28.
    C.H. Moon, K.S. Oh, J.D. Lee, S.J. Lee and Y. Lee: ISIJ Int., 2012, vol. 52, pp. 1266-72.CrossRefGoogle Scholar
  29. 29.
    M. Tanaka, S. Ono and M. Tsuneno: J. Jpn. Soc. Technol. Plast., 1987, vol. 28, pp. 238–44.Google Scholar
  30. 30.
    J.L. Rodgers and W.A. Nicewander: Am. Stat., 1988, vol. 42, pp. 59-66.CrossRefGoogle Scholar

Copyright information

© The Minerals, Metals & Materials Society and ASM International 2019

Authors and Affiliations

  1. 1.Key Laboratory for Ecological Metallurgy of Multimetallic Ores (Ministry of Education)ShenyangP.R. China
  2. 2.School of MetallurgyNortheastern UniversityShenyangP.R. China

Personalised recommendations