Metallurgical and Materials Transactions A

, Volume 44, Issue 11, pp 5177–5191 | Cite as

On the Low Temperature Strain Aging of Bainite in the TRIP Steel

  • Ilana Timokhina
  • Hossein Beladi
  • Xiang-Yuan Xiong
  • Peter D. Hodgson


The aging behavior of a thermomechanically processed Mo-Al-Nb transformation-induced plasticity steel with ultrafine microstructure was investigated using transmission electron microscopy and atom probe tomography (APT). Strain aging at 73 K (200 °C) for 1800 seconds led to a significant bake-hardening response (up to 222 MPa). Moreover, aging for 1800 seconds at room temperature after 4 pct pre-strain also revealed a bake-hardening response (~60 MPa). The experimental results showed the formation of carbon Cottrell atmospheres around dislocations and the formation of carbon clusters/fine carbides in the bainitic ferrite during aging. It is proposed that this is associated with the high dislocation density of bainitic ferrite with formation of a complex dislocation substructure after pre-straining and its high average carbon content (~0.35 at. pct). The segregation of carbon and substitutional elements such as Mn and Mo to the retained austenite/bainitic ferrite interface during aging was observed by APT. This segregation is likely to be the preliminary stage for Mo-C particles’ formation. The aging after pre-straining also induced the decomposition of retained austenite with formation of ferrite and carbides.


  1. 1.
    L. Samek, E. De Moor, J. Penning, J.G. Speer and B.C. De Cooman: Metall. Mater. Trans. A, 2008, Vol. 39A, pp. 2543–53.Google Scholar
  2. 2.
    T. Waterschoot, A.K. De, S. Vandeputte and B.C. De Cooman: Metall. Mater. Trans. A, 2003, Vol. 34A, pp. 781–91.Google Scholar
  3. 3.
    I.B. Timokhina, P.D. Hodgson, E.V. Pereloma: Metall. Mater. Trans. A, 2007; Vol. 38A, pp. 2442–57.CrossRefGoogle Scholar
  4. 4.
    L.J. Baker, S.R. Daniel, J.D. Parker: Mater. Sci. Technol., 2002, Vol. 18, 355–68.CrossRefGoogle Scholar
  5. 5.
    B.C. De Cooman (2004) Curr. Opin. Solid State Mater. Sci. 8:285–303.CrossRefGoogle Scholar
  6. 6.
    I.B. Timokhina, M. Enomoto, M.K. Miller and E.V. Pereloma: Metall. Mater. Trans. A, 2012, Vol. 43A, pp. 2473–83.CrossRefGoogle Scholar
  7. 7.
    E.V. Pereloma, K.F. Russell, M.K. Miller and I.B. Timokhina: Scripta Mater., 2008, Vol. 58, pp. 1078–81.CrossRefGoogle Scholar
  8. 8.
    E.F. Rauch, S. Thuillier: Mater. Sci. Eng. A, 1993, 164, pp. 255–59.CrossRefGoogle Scholar
  9. 9.
    S. Thuillier, E.F. Rauch: Acta Metall. Mater., 1994, 42(6), pp. 1973–83.CrossRefGoogle Scholar
  10. 10.
    I.B. Timokhina, H. Beladi, X.Y. Xiong, P.D. Hodgson: Materials Science Forum, 2012; 706–709: pp. 2332–35.CrossRefGoogle Scholar
  11. 11.
    I.B. Timokhina: Ph.D. Thesis, Deakin University, Australia, 2003, pp. 82–118.Google Scholar
  12. 12.
    E.V. Pereloma, I.B. Timokhina, M.K. Miller and P.D. Hodgson: Acta Mater., 2007, Vol. 55, pp. 2587–98.CrossRefGoogle Scholar
  13. 13.
    B.D. Cullity: Elements of X-Ray Diffraction, New York: Addison-Wesley, 1978, p. 555.Google Scholar
  14. 14.
    P.B. Hirsch, R.B. Nicholson, A. Howie, D.W. Pashley and M.J. Whelan: Electron Microscopy of Thin Crystals. Butterworths, London, 1965, p. 51.Google Scholar
  15. 15.
    P.M. Kelly, A. Jostsons, R.G. Blake and J.G. Napier: Phys. Status Solidi, 1975, 31, p. 771.CrossRefGoogle Scholar
  16. 16.
    M.K. Miller: Atom Probe Tomography, New York, Kluwer Academic Press, 2005.Google Scholar
  17. 17.
    I. Tsukatani, S. Hashimoto and T. Innoue: ISIJ International, 1991, Vol. 31, No 9, pp. 992–1000.CrossRefGoogle Scholar
  18. 18.
    Y. Tommita: Mater. Sci., 1995, Vol. 30, pp. 105–110.Google Scholar
  19. 19.
    I.B. Timokhina, P.D. Hodgson, E.V. Pereloma: Metall. Mater. Trans. A, 2003, Vol. 34A, pp. 1599–1609.CrossRefGoogle Scholar
  20. 20.
    H.K.D.H. Bhadeshia and D. Edmonds: Metall. Trans. A, 1979, Vol. 10A, pp. 895–907.Google Scholar
  21. 21.
    H.K.D.H. Bhadeshia: Bainite in Steels. The Institute of Materials, Cambridge University Press, Cambridge; 1992.Google Scholar
  22. 22.
    M. Onink, C.M. Brakman, F.D. Tichelaar, E.J. Mittemeijer, S. van der Zwaag and N.B. Konyer (1993) Scripta Metall. Mater. 29(8):1011–16.CrossRefGoogle Scholar
  23. 23.
    I.B. Timokhina, E.V. Pereloma, P.D. Hodgson, M. Militzer, W.J. Poole, and E. Essadiqi eds.: 42 nd Conference Proceedings of CIM 2003, Transformation and Deformation Mechanisms in Advanced High Strength Steels, 2003, Vancouver, Canada, Canadian Institute of Mining, Metals and Petroleum 6, CD-ROM, pp. 331–35.Google Scholar
  24. 24.
    I.B. Timokhina, H. Beladi, X.Y. Xiong, Y. Adachi, P.D. Hodgson: Acta Mater., 2011, Vol. 59, pp. 5511–22.CrossRefGoogle Scholar
  25. 25.
    I.B. Timokhina, E.V. Pereloma, S.P. Ringer, R.K. Zheng, P.D. Hodgson: ISIJ International, 2010, Vol. 50 (4), pp. 574–82.CrossRefGoogle Scholar
  26. 26.
    I.B. Timokhina, P.D. Hodgson and E.V. Pereloma: Metall. Mater. Trans. A, 2004, Vol. 35A, pp. 2331–41.CrossRefGoogle Scholar
  27. 27.
    J.J. Gracio: Mater. Sci. Eng. A, 1994, Vol. 174, pp. 111–19.CrossRefGoogle Scholar
  28. 28.
    N.A. Gjostein (1963) Metal Surfaces. ASM, Metals Park, OH, pp. 99–154.Google Scholar
  29. 29.
    G. Neumann and G.M. Neumann: Surface Self-Diffusion of Metals, Diffusion Monograph Series, F.H. Wohlbier, ed., 1972, vol. 1, p. 69.Google Scholar
  30. 30.
    A.H. Cottrell, B.A. Bilby: Proc. Phys. Soc., 1949, 63, pp. 49–62.Google Scholar
  31. 31.
    D. Kalish, M. Cohen: Mater. Sci. Eng., Vol. 6, 1970, p. 156–61.CrossRefGoogle Scholar
  32. 32.
    B.P. Sandvik: Metall. Trans. A, 1982, Vol. 13A, pp. 789–806.Google Scholar
  33. 33.
    T. Nakamura and S. Nagakura: International Conference on Martensite Transformation, ICOMAT 86, Japan Institute of Metals, Sendai, 1986, pp. 386–91.Google Scholar

Copyright information

© The Minerals, Metals & Materials Society and ASM International 2013

Authors and Affiliations

  • Ilana Timokhina
    • 1
  • Hossein Beladi
    • 1
  • Xiang-Yuan Xiong
    • 2
  • Peter D. Hodgson
    • 3
  1. 1.Institute for Frontier Materials, GTP Research, Geelong Technology PrecinctDeakin UniversityGeelongAustralia
  2. 2.Centre for Electron MicroscopyMonash UniversityClaytonAustralia
  3. 3.Institute for Technology Research and InnovationDeakin UniversityGeelongAustralia

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