Factors Limiting the Achievable Ferrite Grain Refinement in Hot Worked Microalloyed Steels

Abstract:

Nb is added to C-Mn steels in order to use the solute drag and/or strain induced precipitation as a useful tool to condition the austenite in the hot rolling mill and produce during the subsequent cooling a refined ferrite grain size. The highest degree of refinement is obtained in conventional rolling mills by accumulating the deformation in austenite during the last passes, followed by early cooling in the run out table to produce a high density of nucleated ferrite grains. However, the maximum refinement is to a certain extent attenuated due to the ferrite grain coarsening taking place during the transformation. The present work analyses the different aspects limiting the final achievable ferrite grain refinement.

• Periodical: Materials Science Forum (Volumes 500-501)
• Pages: 355-362
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.500-501.355
• Online since: November 2005
• Authors: E. Novillo, E. Cotrina, Amaia Iza-Mendia, Beatriz López, Isabel Gutiérrez
• Keywords: Ferrite Grain Coarsening, Ferrite Grain Refinement , Hot Working, Microalloyed, Transformation

References

[1] F. Pickering: Physical metallurgy and design of steels, Applied Science Publishers Ltd, Barking, Essex, United Kingdom, (1978).

[2] S.S. Hansen: Metall. Mater. Trans. A Vol. 11 (1980), p.387.

[3] A.I. Fernández, P. Uranga, B. López and J.M. Rodriguez-Ibabe: ISIJ Intern. Vol. 40 (2000), p.893.

[4] R. Bengoechea, B. López and I. Gutierrez: Metall. and Mater. Trans. Vol. 29 (1998), p.417.

[5] E. Cotrina, A. Argüelles, R. Bengochea, B. López and I . Gutierrez: Proc. Int. Conf. Thermomechanical Processing of Steels (Institute of Metals, London, 2000), p.255.

[6] E Cotrina, A-Iza-Media, B. López and I. Gutiérrez: Metall. Mater. Trans. A Vol. 35 (2003), p.93.

[7] E. Novillo, D. Hernández , I. Gutiérrez and B. López: Mater. Sci. Eng. A Vol 385 (2004), p.83.

[8] D.R. Barraclough, H.J. Whitaker, K.D. Nair and C.M. Sellars: J. Test. Eval. Vol. 1 (1973), p.220.

[9] D.W. Suh, J.H. Kang, K.H. Oh and H.C. Lee: Scripta Mater. Vol. 46 (2002), p.375.

[10] D. Hernández, M. Diaz-Fuentes, B. Lopez and J. M. Rodriguez-Ibabe: Mat. Sci. Forum Vol. 426-432 (2003), p.1151.

[11] T. Kimura, F. Kawabata, K. Amano, A. Ohmori, M. Okatsu and K. Uchida: Proc. International Symposium on Steel for Fabricated Structures, (ASM 1999), p.165.

[12] D. Hernández, B. López and J.M. Rodriguez-Ibabe: Proc. Microalloyed Steels 2002, R.I. Asfahani, R. L. Bodnar and M.J. Merwin (2002), p.64.

[13] D. Jorge-Badiola, A. Iza-Mendia, I. Gutiérrez: Mater. Sci. Eng A, Available online, Jan. (2005).

[14] F. Bai, P. Cizek, E.J. Palmiere and W.M. Rainforth: Mat. Sci. Forum Vol. 467-470 (2004), p.21.

[15] D.A. Porter and K.E. Easterling: Phase transformations in metals and alloys, Chapman & Hall, London (1981), p.317.

[16] A. F. Gourgues, H. M. Flower and T. C. Lindley: Mater. Sci. Technol. Vol. 16 (2000), p.26.

[17] M. Díaz, A. Iza-Mendia and I. Gutiérrez: Metall. Mater. Trans. A Vol. 34 (2003), p.2505.

[18] T. Furuhara and T. Maki: Mater. Trans. Vol. 33 (1992), p.734.

[19] T. Furuhara, J.M. Howe and H.I. Aaronson: Acta Metall. Mater. Vol. 39 (1991), p.2873.

[20] J.F. Nie, B.C. Muddle, T. Furuhara and H.I. Aaronson: Scr. Mater. Vol. 39 (1998), p.637.

[21] K. Ameyama and T. Maki: Scr. Mater. Vol. 24 (1990), p.173.

[22] J.C.M. Li: J. Appl. Phys. Vol. 33 (1962), p.2958.

[23] R.D. Doherty and J.A. Szpunar: Acta Metall. Vol. 32 (1984), p.1789.

[24] M. Lübbehusen and H. Mehrer: Acta Metal. Mater. Vol. 38 (1990), p.283.