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.
This is a preview of subscription content, access via your institution.
Buy single article
Instant access to the full article PDF.
Tax calculation will be finalised during checkout.
Subscribe to journal
Immediate online access to all issues from 2019. Subscription will auto renew annually.
Tax calculation will be finalised during checkout.
H. Kakimoto, T. Arikawa, Y. Takahashi, T. Tanaka and Y. Imaida: J. Mater. Process. Technol., 2010, vol. 210, pp. 415–22.
Y.S. Lee, S.U. Lee, C.J. Van Tyne and B.D. Joo: J. Mater. Process. Technol., 2011, vol. 211, pp. 1136-45.
J.J. Park: ISIJ Int., 2013, vol. 53, pp. 1420-6.
M.S. Chen and Y.C. Lin: Int. J. Plast., 2013, vol. 49, pp. 53-70.
D.C. Chen: J. Mater. Process. Technol., 2006, vol. 180, pp. 193-200.
M. Nakasaki, I. Takasu and H. Utsunomiya: J. Mater. Process. Technol., 2006, vol. 177, pp. 521-4.
J. Chen, K. Chandrashekhara, C. Mahimkar, S.N. Lekakh and V.L. Richards: J. Mater. Process. Technol., 2011, vol. 211, pp. 245-55.
G.S. Li, W. Yu and Q.W. Cai: Metall. Mater. Trans. B, 2015, vol. 46, pp. 831-40.
G.S. Li, W. Yu and Q. Cai: J. Mater. Process. Technol., 2016, vol. 227, pp. 41-8.
J.J. Park: Metall. Mater. Trans. A, 2016, vol. 47, pp. 479-87.
X.K. Zhao, J.M. Zhang, S.W. Lei and Y.N. Wang: Steel Res. Int., 2014, vol. 85, pp. 1533-43.
Z.G. Xu, X.H. Wang and M. Jiang: Steel Res. Int., 2017, vol. 88, pp. 231-42.
Q.P. Dong, J.M. Zhang, B. Wang and X.K. Zhao: J. Mater. Process. Technol., 2016, vol. 238, pp. 81-8.
J.P. Zhao, L. Liu, W.W. Wang and H. Lu: Ironmaking Steelmaking, 2017, https://doi.org/10.1080/03019233.2017.1366090.
C. Ji, C.H. Wu and M.Y. Zhu: JOM, 2016, vol. 68, pp. 3107-15.
C. Ji, G.L. Li, C.H. Wu and M.Y. Zhu: Metall. Mater. Trans. B, 2019, vol. 50, pp. 110-22.
C.H. Wu, C. Ji and M.Y. Zhu: J. Mater. Process. Technol., 2019, vol. 271, pp. 651-9.
K. Miyazawa and K. Schwerdtfeger: rch. Eisenhuettenwes., 1981, vol. 52, pp. 415–22.
T. Kajitani, J.-M. Drezet, and M. Rappaz: Metall. Mater. Trans. A, 2001, vol. 32A, pp. 1479-91.
M. Wu, J. Domitner, and A. Ludwig: Metall. Mater. Trans. A, 2012, vol. 43A, pp. 945-64.
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.
M. Wu, and A. Ludwig: Metall. Mater. Trans. A, 2006, vol. 37, pp. 1613–31.
R. Guan, C. Ji, M.Y. Zhu, and S.M. Deng, Metall. Mater. Trans. B, 2018, vol. 49, pp. 2571–83.
R. Guan, C. Ji, C. H. Wu, and M. Y. Zhu, Int. J. Heat Mass Transfer, 2019, vol. 141, pp. 503-16.
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.
C. Ji, S. Luo and M.Y. Zhu: ISIJ Int., 2014, vol. 54, pp. 504-10.
C. Ji, Z.L. Wang, C.H. Wu and M.Y. Zhu: Metall. Mater. Trans. B, 2018, vol. 49, pp. 767-82.
C.H. Moon, K.S. Oh, J.D. Lee, S.J. Lee and Y. Lee: ISIJ Int., 2012, vol. 52, pp. 1266-72.
M. Tanaka, S. Ono and M. Tsuneno: J. Jpn. Soc. Technol. Plast., 1987, vol. 28, pp. 238–44.
J.L. Rodgers and W.A. Nicewander: Am. Stat., 1988, vol. 42, pp. 59-66.
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.
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Manuscript submitted December 28, 2018.
About this article
Cite this article
Wu, C., Ji, C. & Zhu, M. Closure of Internal Porosity in Continuous Casting Bloom During Heavy Reduction Process. Metall Mater Trans B 50, 2867–2883 (2019). https://doi.org/10.1007/s11663-019-01692-z