Metallurgical and Materials Transactions A

, Volume 29, Issue 2, pp 577–586 | Cite as

Role of microstructural degradation in the heat-affected zone of 2.25Cr-1Mo steel weldments on subscale features during steam oxidation and their role in weld failures

  • R. K. Singh Raman


Microstructural degradations in the base metal adjacent to the weld pool, i.e., the heat-affected zone (HAZ), caused during welding of 2.25Cr-1Mo steel, were characterized by electron and optical microscopy of different regions of the weldments. In order to study the influence of the microstructural degradations on scaling kinetics in steam and the resulting subscale features, samples of the base metal, the HAZ, and weld metal specimens were extracted from the weldment and oxidized in an environment of 35 pct steam+nitrogen at 873 K for 10 hours. Oxide scales formed in the three regions and the underlying subscales were characterized using scanning electron microscopy (SEM) and electron probe microanalysis (EPMA). Influence of the “free” chromium content in the three weldment regions on protective scale formation and on the subscale features has been investigated. As the principal achievement, this study has clearly shown the occurrence of oxidation-induced void formation in the subscale zone and grain boundary cavitation in the neighboring area during steam oxidation of the HAZ. This article also discusses the possible role of oxidation-induced void formation and grain boundary cavitation in the inferior service life of welds in 2.25Cr-1Mo steel components.


Material Transaction Base Metal Weld Metal Oxide Scale Alloy Matrix 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    Ferritic Steels for High Temperature Applications: ASM Int. Conf., Warren, PA, 1981, A.K. Khare, ed, American Soc. of Metals, OH.Google Scholar
  2. 2.
    Proc. BNES Int. Conf. Ferritic Steels for Fast Reactor Steam Generators, S.F. Pugh and E.A. Little, eds., BNES, London, 1978.Google Scholar
  3. 3.
    Ferrinc Steels for High Temperature Applications: ASM Int. Conf., Warren, PA, 1981, T. Wada, G.T. Eldis, and A.K. Khare, eds., American Soc. of Metals, OH, p. 8S.Google Scholar
  4. 4.
    J. Bland: Weld. J.-Res. Suppl., 1956, vol. 35, p. 181s.Google Scholar
  5. 5.
    L.S. Mandich, E.L. Fogelmen, and J.A. Gulya: Symp. Heat treated Steel for Elevated Temperature Services ASME, New Orleans, LA, 1956.Google Scholar
  6. 6.
    E.W. Colebeck and J.R. Rait: “High Temperature Steel and Alloys for Gas Turbines,” 1st Special Report No. 43, 1952, p. 107.Google Scholar
  7. 7.
    K. Laha, K.B.S. Rao, and S.L. Mannan: Mater. Sci. Eng., 1990, A129, pp. 183–95.Google Scholar
  8. 8.
    “ASME Boiler and Pressure Vessel Code,” Code Case N-47, ASME, Fairfield, NJ. 1986.Google Scholar
  9. 9.
    B. Chew and P. Harris: Met. Construction, 1979, May, p. 11.Google Scholar
  10. 10.
    P. Roy and T. Lauritzen: Weld. J.-Res. Suppl., 1986, vol. 65, p. 45s.Google Scholar
  11. 11.
    S.D. Mann and B.C. Muddle: Proc. Microstructure and Mechanical Properties of Aging Material, TMS, Warrendale, PA, 1993, pp. 301–08.Google Scholar
  12. 12.
    R.K. Singh Raman, A.S. Khanna, R.K. Tiwari, and J.B. Gnanamoorthy: Oxid. Met., 1992, vol. 37, pp. 1–12.CrossRefGoogle Scholar
  13. 13.
    R.K. Singh Raman and J.B. Gnanamoorthy: J. Mater. Sci., 1992, vol. 27, pp. 3435–41.CrossRefGoogle Scholar
  14. 14.
    R.K. Singh Raman: Metall. Mater. Trans. A, 1995, vol. 26, pp. 1847–58.Google Scholar
  15. 15.
    N. Birks and G.M. Meyer: Introduction to High Temperature Oxidation of Metals, Edward Arnold, London, 1982.Google Scholar
  16. 16.
    C. Phaniraj, M. Valson, S.L. Mannan, and P. Rodriguez: Proc. Workshop on Oxidation of Metals and Alloys, Indian Institute of Metals, Kalpakkam Branch, India, 1984, p. 171.Google Scholar
  17. 17.
    P. Rodriguez: Trans. Ind. Inst. Met., 1967, vol. 20, p. 213.Google Scholar
  18. 18.
    P. Shahinian: Trans. ASM, 1957, vol. 49, p. 862.Google Scholar
  19. 19.
    R. Widmer and N.J. Grant: Trans. ASME, 1960, vol. D82, p. 882.Google Scholar
  20. 20.
    H.E. McCoy, W.R. Martin, and J.R. Weir: Proc. Institute of Environmental Science, 1961, p. 163.Google Scholar
  21. 21.
    I.R. Kramer and N. Balasubramanian: Metall Trans., 1973, vol. 2, pp. 431–36.Google Scholar
  22. 22.
    W.R. Johnson, C.R. Barrett, and W.D. Nix: Metall. Trans., 1972, vol. 3, pp. 695–98.Google Scholar
  23. 23.
    B.J. Smith and A.R. Marder: Corrosion, 1992, vol. 48, p. 29.CrossRefGoogle Scholar
  24. 24.
    R.L. Klueh and J.F. King: Weld. J.-Res. Suppl., 1982, vol. 61, p. 302s.Google Scholar
  25. 25.
    R.K. Singh Raman and J.B. Gnanamoorthy: Corr. Sci., 1993, vol. 43, pp. 1275–88.CrossRefGoogle Scholar
  26. 26.
    H. Howarth: Corrosion, L.L. Shrier, ed., Newnes-Butterworths, London, 1976, vol. I, pp. 7:13–7:44.Google Scholar
  27. 27.
    J. Pilling and N. Ridley: Metall. Trans. A, 1982, vol. 13A, pp. 557–63.Google Scholar
  28. 28.
    M.E. El-Dahshan, J. Stringer, and D.P. Whittle: Cobalt, 1974, vol. 4, p. 86.Google Scholar
  29. 29.
    R.N. Durham, B. Gleeson, and D.J. Young: Proc. 13th Int. Corrosion Conf., Melbourne, Australian Corrosion Association, Melbourne, 1996, pp. 1–10.Google Scholar
  30. 30.
    R.K. Singh Raman, A.S. Khanna, B.K. Choudhary, and J.B. Gnanamoorthy: Mater. Sci. Eng. A, 1991, vol. 148, pp. 299–306.CrossRefGoogle Scholar
  31. 31.
    S. Leistikow, I. Wolf, and H.J. Grabke: Werkst. Korros., 1987, vol. 38, p. 556.CrossRefGoogle Scholar
  32. 32.
    Y. Shida, N. Ohtsunaka, J. Murayama, N. Fujino, and H. Fujikawa: Proc. JIMS-3: High Temperature Corrosion; appeared in Trans. Jpn. Inst. Met., 1983, vol. 63.Google Scholar
  33. 33.
    R.K. Singh Raman, A.S. Khanna, and J.B. Gnanamoorthy: Proc. 1st Int. Conf. on Microscopy of Oxidation, M.J. Bennett and G.W. Lorimer, eds., The Inst. of Materials, London, Cambridge, United Kingdom, 1990, pp. 54–58.Google Scholar
  34. 34.
    L. Tomlinson and N.J. Cory: Corros. Sci., 1989, vol. 29, p. 939.CrossRefGoogle Scholar
  35. 35.
    P.L. Surman and J.E. Castle: Corros. Sci., 1969, vol. 9, p. 771.CrossRefGoogle Scholar
  36. 36.
    I.E. Klein, J. Sharaon, and A.E. Yaniv: Scripta Metall., 1981, vol. 15, p. 141.CrossRefGoogle Scholar
  37. 37.
    P. Mayer and A.V. Manolescu: High Temperature Corrosion, NACE, Tokyo, 1981, p. 368.Google Scholar
  38. 38.
    P.H. Effertz: Proc. 5th Int. Congr. Metallic Corrosion, NACE, Tokyo, 1972, p. 920.Google Scholar
  39. 39.
    N.J. Cory and T.H. Herrington: Oxid. Met., 1987, vol. 28, p. 237.CrossRefGoogle Scholar
  40. 40.
    R. Rolls and J.H. Cleland: Phil. Mag. A, 1981, vol. 44, p. 943.Google Scholar
  41. 41.
    P. Hancock: Vancancies 76, R.E. Smallmen and J.E. Harris, eds., The Metals Society, London, 1977, p. 215.Google Scholar
  42. 42.
    E.C. Scaife and P.L. James: Met. Sci. J., 1968, vol. 2, p. 217.CrossRefGoogle Scholar
  43. 43.
    H.H. Bleakney: Can. J. Technol., 1952, vol. 30, p. 340.Google Scholar
  44. 44.
    C.E. Price: Acta Metall., 1966, vol. 14, p. 1787.CrossRefGoogle Scholar

Copyright information

© ASM International & TMS-The Minerals, Metals and Materials Society 1998

Authors and Affiliations

  • R. K. Singh Raman
    • 1
  1. 1.the Department of Communication and Electronic EngineeringRoyal Melbourne Institute of Technology (RMIT)MelbourneAustralia

Personalised recommendations