An Investigation of Columnar to Equiaxed Transition and the Effect of Cooling Rate on Nucleus Density Distribution of an Industrial Ti and Nb-Stabilized Ferritic Stainless Steel


The heterogeneous nucleus distribution of an industrial Ti and Nb-stabilized ferritic stainless steel (FSS) with high-equiaxed zone ratio was investigated in detail. The heterogeneous nucleus is the complex nucleus mainly composed of central Ti-containing oxide and external (Ti,Nb)(CN). A “V” type distribution of complex nucleus was revealed in the thickness direction, indicating that the nucleus density decreases as the slab solidifies. A “W” type distribution of equiaxed crystals was also observed in the thickness direction. A linear relationship between equiaxed crystal density and nucleus density was obtained in the columnar to equiaxed transition (CET) and quarter position of the slab, indicating that the density of equiaxed crystals is significantly influenced by that of the complex nucleus. Theoretical analysis and confocal laser scanning microscopy experiments were carried out to reveal the distribution mechanism of the complex nucleus. The results showed that the cooling rate has a significant influence on the nucleation undercooling of FSS, which indirectly affects the formation of the complex nucleus. Based on these findings, a numerical model was established to investigate the CET of FSS, and the prediction was in good agreement with the experimental results. According to the numerical model, even if the nucleus density decreases during solidification, it is still sufficient for stimulation of CET.

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  1. 1.

    H.-J. Shin, J.-K. An, S. H. Park and D. N. Lee, Acta Metall., 2003, vol. 51, pp. 4693-706.

    CAS  Google Scholar 

  2. 2.

    J.-i. Hamada, Y. Matsumoto, F. Fudanoki and S. Maeda, ISIJ Int., 2003, vol. 43, pp. 1989-98.

    CAS  Google Scholar 

  3. 3.

    H. Liu, Z. Liu and G. Wang, ISIJ Int., 2009, vol. 49, pp. 890-96.

    CAS  Google Scholar 

  4. 4.

    Y. Shao, C. Liu, T. Yue, Y. Liu, Z. Yan and H. Li, Metall. Mater. Trans. B, 2018, vol. 49, pp. 1560-67.

    Google Scholar 

  5. 5.

    S. Ikeda, Nippon Steel Tech. Rep., 2010, vol. 99, pp. 2-8.

    Google Scholar 

  6. 6.

    Y. Yazawa, Y. Ozaki, Y. Kato and O. Furukimi, JSAE Review, 2003, vol. 24, pp. 483-88.

    CAS  Google Scholar 

  7. 7.

    T. Kawasaki, Kawasaki Steel Tech. Rep., 1999, vol. 40, pp. 5-15.

    Google Scholar 

  8. 8.

    K. Kimura and A. Takahashi, Nippon Steel Tech. Rep., 2010, vol. 99, pp. 51-55.

    Google Scholar 

  9. 9.

    S. Kusunoki, R. Nishihara, K. Kato, H. Sakagami, S. Hirashima, and N. Fukunaga: Nippon Steel Tech. Rep., 2013, vol. 104.

  10. 10.

    Q. Rui, F. Jiang, Z. Ma, Z. You, G. Cheng and J. Zhang, Steel Res. Int., 2013, vol. 84, pp. 192-97.

    CAS  Google Scholar 

  11. 11.

    Z. You, G. Cheng, X. Wang, Z. Qin, J. Tian and J. Zhang, Metall. Mater. Trans. B, 2015, vol. 46, pp. 459-72.

    Google Scholar 

  12. 12.

    R. T. J. Hodges, Corros., 1971, vol. 27, pp. 119-27.

    CAS  Google Scholar 

  13. 13.

    H. Tomari, K. Fujiwara, K. Shimogori, T. Fukuzuka and M. Kanda, Corros., 1982, vol. 38, pp. 283-94.

    CAS  Google Scholar 

  14. 14.

    H. Y. Ha, C. J. Park and H. S. Kwon, Corros. Sci., 2007, vol. 49, pp. 1266-75.

    CAS  Google Scholar 

  15. 15.

    J. K. Kim, Y. H. Kim, S. H. Uhm, J. S. Lee and K. Y. Kim, Corros. Sci., 2009, vol. 51, pp. 2716-23.

    CAS  Google Scholar 

  16. 16.

    K. Ishii, T. Ishii, and H. Ota: JFE Tech. Rep., 2008, pp. 39–44.

  17. 17.

    P. Modak, S. Patra, R. Mitra and D. Chakrabarti, Metall. Mater. Trans. A, 2018, vol. 49, pp. 2219-34.

    Google Scholar 

  18. 18.

    S. Park, K. Kim, Y. Lee and C. Park, ISIJ Int., 2002, vol. 42, pp. 100-05.

    CAS  Google Scholar 

  19. 19.

    Y. Hou, S. Li and G. Cheng, Metall. Mater. Trans. A, 2018, vol. 49, pp. 5445-57.

    Google Scholar 

  20. 20.

    M. Brochu, T. Yokota and S. Satoh, ISIJ Int., 1997, vol. 37, pp. 872-77.

    CAS  Google Scholar 

  21. 21.

    Y. Hou and G. Cheng, ISIJ Int., 2018, vol. 58, pp. 2298-307.

    CAS  Google Scholar 

  22. 22.

    A. Ito, H. Suito and R. Inoue, ISIJ Int., 2012, vol. 52, pp. 1196-205.

    CAS  Google Scholar 

  23. 23.

    S. K. Kim, H. Suito and R. Inoue, ISIJ Int., 2012, vol. 52, pp. 1935-44.

    CAS  Google Scholar 

  24. 24.

    K. Kimura, S. Fukumoto, G. Shigesato and A. Takahashi, ISIJ Int., 2013, vol. 53, pp. 2167-75.

    CAS  Google Scholar 

  25. 25.

    J. Mola, I. Jung, J. Park, D. Chae and B. C. de Cooman, Metall. Mater. Trans. A, 2012, vol. 43, pp. 228-44.

    Google Scholar 

  26. 26.

    J. Fu, W. Qiu, Q. Nie and Y. Wu, J. Alloys Compd., 2017, vol. 699, pp. 938-46.

    CAS  Google Scholar 

  27. 27.

    C.-x. Shi, G.-g. Cheng, Z.-j. Li and P. Zhao, J. Iron Steel Res. Int., 2008, vol. 15, pp. 57-60.

    CAS  Google Scholar 

  28. 28.

    J. C. Villafuerte, H. W. Kerr and S. A. David, Mater. Sci. Eng. A, 1995, vol. 194, pp. 187-91.

    Google Scholar 

  29. 29.

    J. C. Villafuerte, E. Pardo and H. W. Kerr, Metall. Trans. A, 1990, vol. 21, pp. 2009-19.

    Google Scholar 

  30. 30.

    H. Fujimura, S. Tsuge, Y. Komizo and T. Nishizawa, Tetsu-to-Hagane, 2001, vol. 87, pp. 707-12.

    CAS  Google Scholar 

  31. 31.

    A. Hunter and M. Ferry, Metall. Mater. Trans. A, 2002, vol. 33, pp. 1499-507.

    CAS  Google Scholar 

  32. 32.

    J. Y. Kim, N. R. Oh, Y. H. Oh, Y. T. Cho, W. B. Lee, S. K. Kim and H. U. Hong, Mater. Charact., 2017, vol. 132, pp. 348-53.

    CAS  Google Scholar 

  33. 33.

    J. S. Park, D. H. Kim and J. H. Park, J. Alloys Compd., 2017, vol. 695, pp. 476-81.

    CAS  Google Scholar 

  34. 34.

    Y. Hou and G. Cheng, Metall. Mater. Trans. B, 2019, vol. 50, pp. 1322-33.

    Google Scholar 

  35. 35.

    Y. Hou and G. Cheng, Metall. Mater. Trans. B, 2019, vol. 50, pp. 1351-64.

    Google Scholar 

  36. 36.

    L. Bai, B. Wang, H. Zhong, J. Ni, Q. Zhai and J. Zhang, Metals, 2016, vol. 6, pp. 53-64.

    Google Scholar 

  37. 37.

    H. Shibata, S. Itoyama, Y. Kishimoto, S. Takeuchi and H. Sekiguchi, ISIJ Int., 2006, vol. 46, pp. 921-30.

    CAS  Google Scholar 

  38. 38.

    S. Ogibayashi: Nippon Steel Tech. Rep., 1994, pp. 70–76.

  39. 39.

    M. Gäumann, R. Trivedi and W. Kurz, Mater. Sci. Eng. A, 1997, vol. 226, pp. 763-69.

    Google Scholar 

  40. 40.

    D.A. Porter, K.E. Easterling, and M. Sherif: Phase Transformations in Metals and Alloys, (Revised Reprint). (CRC Press, Boca Raton, 2009).

  41. 41.

    Z. Hou, F. Jiang and G. Cheng, ISIJ Int., 2012, vol. 52, pp. 1301-09.

    CAS  Google Scholar 

  42. 42.

    X. Gao, S. Yang and J. Li, Mater. Design, 2016, vol. 110, pp. 284-95.

    CAS  Google Scholar 

  43. 43.

    H. Takeuchi, Y. Ikehara, T. Yanai and S. Matsumura, Tetsu-to-Hagane, 1977, vol. 63, pp. 1287-96.

    CAS  Google Scholar 

  44. 44.

    J. H. Park, S.-B. Lee and H. R. Gaye, Metall. Mater. Trans. B, 2008, vol. 39, pp. 853-61.

    CAS  Google Scholar 

  45. 45.

    J. H. Park and H. Todoroki, ISIJ Int., 2010, vol. 50, pp. 1333-46.

    CAS  Google Scholar 

  46. 46.

    J. H. Park, Calphad, 2011, vol. 35, pp. 455-62.

    CAS  Google Scholar 

  47. 47.

    J. S. Park and J. H. Park, Steel Res. Int., 2014, vol. 85, pp. 1303-09.

    CAS  Google Scholar 

  48. 48.

    D. Kashchiev, A. Borissova, R. B. Hammond and K. J. Roberts, J. Cryst. Growth, 2010, vol. 312, pp. 698-704.

    CAS  Google Scholar 

  49. 49.

    B. L. Bramfitt, Metall. Trans., 1970, vol. 1, pp. 1987-95.

    CAS  Google Scholar 

  50. 50.

    J. S. Park, C. Lee and J. H. Park, Metall. Mater. Trans. B, 2012, vol. 43, pp. 1550-64.

    Google Scholar 

  51. 51.

    J. A. Spittle, Int. Mater. Rev., 2006, vol. 51, pp. 247-69.

    CAS  Google Scholar 

  52. 52.

    J. K. Brimacombe and K. Sorimachi, Metall. Trans. B, 1977, vol. 8, pp. 489-505.

    Google Scholar 

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This work was supported by the National Natural Science Foundation of China [Project Grant No. 51374020]

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Correspondence to Guoguang Cheng.

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Manuscript submitted May 16, 2019.

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Hou, Y., Cheng, G. An Investigation of Columnar to Equiaxed Transition and the Effect of Cooling Rate on Nucleus Density Distribution of an Industrial Ti and Nb-Stabilized Ferritic Stainless Steel. Metall Mater Trans A 50, 4686–4700 (2019).

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