Transmission Electron Microscopy Studies of Plasma Arc-Welded DP600 Dual-Phase Steel in Keyhole Mode

  • Amit A. Kuril
  • M. Jagannatham
  • G. D. Janaki Ram
  • Srinivasa R. BakshiEmail author


Microstructural characteristics of keyhole plasma arc-welded DP600 steel were analyzed using optical microscopy, scanning electron microscopy, and analytical transmission electron microscopy. The fusion zone (FZ) was observed to consist of allotriomorphic, Widmanstätten, and acicular ferrite along with bainite and martensite leading to enhancement in the hardness compared with the base metal. The coarse-grain HAZ consisted of bainite and martensite, while the fine-grain HAZ consisted of bainitic ferrite and tempered martensite. The sub-critical HAZ was found to consist of tempered martensite with reduced density of dislocations and carbide precipitation. This softening resulted in yield point phenomena and failure in the sub-critical HAZ during the transverse tensile test of welds. The non-isothermal tempering resulted in retarded cementite precipitation due to inadequate time for diffusion of carbon, which led to the lowest hardness of 168 HV0.5 in the sub-critical HAZ. The different features in the FZ and HAZ and their correlation with mechanical properties are discussed.



One of the authors (S.R. Bakshi) acknowledges funding from Institute Research and Development Award (Junior Level) of IIT Madras (MET/16-17/839/RFIR/SRRB) for carrying out the work. Authors also acknowledge funding received from Centre of Excellence in Steel Technology (MET/16-17/148/MSTE/HODX) for funding the studies.


  1. 1.
    Y. Liu, D. Dong, L. Wang, X. Chu, P. Wang, and M. Jin: Mater. Sci. Eng. A, 2015, vol. 627, pp. 296–305.CrossRefGoogle Scholar
  2. 2.
    D. Dong, Y. Liu, Y. Yang, J. Li, M. Ma, and T. Jiang: Mater. Sci. Eng. A, 2014, vol. 594, pp. 17–25.CrossRefGoogle Scholar
  3. 3.
    R. Ashiri, H. Mostaan, and Y. D. Park: Metall. Mater. Trans. A Phys. Metall. Mater. Sci., 2018, vol. 49A, pp. 6161–72.CrossRefGoogle Scholar
  4. 4.
    R. Ashiri, M.A. Haque, C.W. Ji, M. Shamanian, H.R. Salimijazi, and Y. Do Park: Scr. Mater., 2015, vol. 109, pp. 6–10.CrossRefGoogle Scholar
  5. 5.
    R. Ashiri, M. Shamanian, H.R. Salimijazi, M.A. Haque, J.H. Bae, C.W. Ji, K.G. Chin, and Y. Do Park: Scr. Mater., 2016, vol. 114, pp. 41–7.CrossRefGoogle Scholar
  6. 6.
    M.R.U. Ahsan, Y.R. Kim, C.H. Kim, J.W. Kim, R. Ashiri, and Y.D. Park: Sci. Technol. Weld. Join., 2016, vol. 21, pp. 209–15.CrossRefGoogle Scholar
  7. 7.
    S. Li, Y. Kang, G. Zhu, and S. Kuang: Mater. Des., 2015, vol. 85, pp. 180–9.CrossRefGoogle Scholar
  8. 8.
    H. Ashrafi, M. Shamanian, R. Emadi, and N. Saeidi: J. Mater. Eng. Perform., 2017, vol. 26, pp. 1414–23.CrossRefGoogle Scholar
  9. 9.
    G.K. Ahiale, Y.-J. Oh, W.-D. Choi, K.-B. Lee, J.-G. Jung, and S.W. Nam: Met. Mater. Int., 2013, vol. 19, pp. 933–9.CrossRefGoogle Scholar
  10. 10.
    N. Sreenivasan, M. Xia, S. Lawson, and Y. Zhou: J. Eng. Mater. Technol., 2008, vol. 130, p. 041004.CrossRefGoogle Scholar
  11. 11.
    S.K. Panda, N. Sreenivasan, M.L. Kuntz, and Y. Zhou: J. Eng. Mater. Technol., 2008, vol. 130, p. 041003.CrossRefGoogle Scholar
  12. 12.
    J.H. Lee, S.H. Park, H.S. Kwon, G.S. Kim, and C.S. Lee: Mater. Des., 2014, vol. 64, pp. 559–65.CrossRefGoogle Scholar
  13. 13.
    J. Wang, L. Yang, M. Sun, T. Liu, and H. Li: Mater. Des., 2016, vol. 97, pp. 118–25.CrossRefGoogle Scholar
  14. 14.
    V.H. Baltazar, S.S. Nayak, and Y. Zhou: Metall. Mater. Trans. A, 2011, vol. 42, pp. 3115–29.CrossRefGoogle Scholar
  15. 15.
    A.A. Kuril, G.D.J. Ram, and S.R. Bakshi: J. Mater. Process. Technol., 2019, vol. 270, pp. 28–36.CrossRefGoogle Scholar
  16. 16.
    C.N. Li, G. Yuan, F.Q. Ji, D.S. Ren, and G.D. Wang: Mater. Sci. Eng. A, 2016, vol. 665, pp. 98–107.CrossRefGoogle Scholar
  17. 17.
    J. Moerman, P.R. Triguero, C. Tasan, and P. van Liempt: Mater. Sci. Forum, 2011, vol. 702–703, pp. 485–8.CrossRefGoogle Scholar
  18. 18.
    S. Gündüz and A. Tosun: Mater. Des., 2008, vol. 29, pp. 1914–8.CrossRefGoogle Scholar
  19. 19.
    J. Kadkhodapour, S. Schmauder, D. Raabe, S. Ziaei-Rad, U. Weber, and M. Calcagnotto: Acta Mater., 2011, vol. 59, pp. 4387–94.CrossRefGoogle Scholar
  20. 20.
    J.K. Martikainen and T.J.I. Moisio: Weld. J. - Weld. Res. Suppl., 1993, 72, pp. 329–40.Google Scholar
  21. 21.
    S. SalimiBeni, M. Atapour, M.R. Salmani, and R. Ashiri: Metall. Mater. Trans. A, 2019, vol. 50A, pp. 2218–34.CrossRefGoogle Scholar
  22. 22.
    C.B. Dallum and D.L. Olson: Weld. J. Res. Suppl., 1989, vol. 68, pp. 198-205.Google Scholar
  23. 23.
    H.K.D.H. Bhadeshia and L.E. Svensson: Math. Model. Weld Phenomena, H. Cerjak E.K. Easterling, eds., Inst. Mater. London, 1993, pp. 109–82.Google Scholar
  24. 24.
    R.D.K. Misra, H. Nathani, J.E. Hartmann, and F. Siciliano: Mater. Sci. Eng. A, 2005, vol. 394, pp. 339–52.CrossRefGoogle Scholar
  25. 25.
    K. Ichikawa, Y. Horii, R. Motomatsu, M. Yamaguchi, and N. Yurioka: J. Japan Weld. Soc., 1996, vol. 14, pp. 27–32.CrossRefGoogle Scholar
  26. 26.
    S. Okaguchi, H. Ohtani, and Y. Ohmori: Mater. Trans., 1991, vol. 32, pp. 697–704.CrossRefGoogle Scholar
  27. 27.
    Y. Ohmori, H. Ohtsubo, Y.C. Jung, S. Okaguchi, and H. Ohtani: Metall. Mater. Trans. A, 1994, vol. 25, pp. 1981–9.CrossRefGoogle Scholar
  28. 28.
    J. Hu, L.X. Du, M. Zang, S.J. Yin, Y.G. Wang, X.Y. Qi, X.H. Gao, and R.D.K. Misra: Mater. Charact., 2016, vol. 118, pp. 446–53.CrossRefGoogle Scholar
  29. 29.
    J.R. Yang, Huang C Y, and Huang C F: J. Mater. Sci. Lett., 1993, vol. 12, pp. 1290–3.CrossRefGoogle Scholar
  30. 30.
    H.K.D.H. Bhadeshia: PhD Thesis. University of Cambridge, 1979.Google Scholar
  31. 31.
    J. Wang and S. Van der Zwaag: Metall. Mater. Trans. A, 2001, vol. 32A, pp. 1527–39.CrossRefGoogle Scholar
  32. 32.
    X.J. Liang, M.J. Hua, and A.J. DeArdo: Mater. Sci. Forum, 2014, vol. 783–786, pp. 704–12.CrossRefGoogle Scholar
  33. 33.
    J. Kobayashi, S.-M. Song, and K. Sugimoto: ISIJ Int., 2012, vol. 52, pp. 1124–9.CrossRefGoogle Scholar
  34. 34.
    N.-R. V. Bangaru and A.K. Sachdev: Metall. Trans. A, 1982, vol. 13A, pp. 1899–906.CrossRefGoogle Scholar
  35. 35.
    J. Smalc-Koziorowska, E. Jezierska, and W. Świątnicki: Solid State Phenom., 2012, vol. 186, pp. 301–4.CrossRefGoogle Scholar
  36. 36.
    H. Beladi, I.B. Timokhina, P.D. Hodgson, and Y. Adachi: Scr. Mater., 2009, vol. 60, pp. 455–8.CrossRefGoogle Scholar
  37. 37.
    F.G. Caballero, M.K. Miller, and C. Garcia-Mateo: Mater. Chem. Phys., 2014, vol. 146, pp. 50–7.CrossRefGoogle Scholar
  38. 38.
    M.Y. Tu, C.A. Hsu, W.H. Wang, and Y.F. Hsu: Mater. Chem. Phys., 2008, vol. 107, pp. 418–25.CrossRefGoogle Scholar
  39. 39.
    T. Furuhara, K. Kobayashi, and T. Maki: ISIJ Int., 2004, vol. 44, pp. 1937–44.CrossRefGoogle Scholar
  40. 40.
    A. Nagao, K. Hayashi, K. Oi, S. Mitao, and N. Shikanai: Mater. Sci. Forum, 2007, vol. 539–543, pp. 4720–5.CrossRefGoogle Scholar
  41. 41.
    S.T. Ahn, D.S. Kim, and W.J. Nam: J. Mater. Process. Technol., 2005, vol. 160, pp. 54–8.CrossRefGoogle Scholar
  42. 42.
    Z.J. Xie, Y.P. Fang, Y. Cui, X.M. Wang, C.J. Shang, and R.D.K. Misra: Mater. Sci. Technol., 2016, vol. 32, pp. 691–6.CrossRefGoogle Scholar
  43. 43.
    E. Biro, J.R. McDermid, J.D. Embury, and Y. Zhou: Metall. Mater. Trans. A Phys. Metall. Mater. Sci., 2010, vol. 41, pp. 2348–56.CrossRefGoogle Scholar

Copyright information

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

Authors and Affiliations

  • Amit A. Kuril
    • 1
  • M. Jagannatham
    • 1
  • G. D. Janaki Ram
    • 1
  • Srinivasa R. Bakshi
    • 1
    Email author
  1. 1.Department of Metallurgical and Materials EngineeringIndian Institute of Technology MadrasChennaiIndia

Personalised recommendations