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Metallurgical and Materials Transactions A

, Volume 45, Issue 13, pp 5923–5936 | Cite as

Precipitate Rafting in a Polycrystalline Superalloy During Compression Creep

  • Arun Altincekic
  • Ercan BalikciEmail author
Article

Abstract

Rafting is an industrially and scientifically important phenomenon for precipitate-strengthened alloys utilized at high temperatures. Although this phenomenon is observed in polycrystalline alloys as well, the literature lacks scientific work on rafting in polycrystals. Scientific work is usually conducted on single-crystal superalloys. Being one of the many polycrystalline nickel-base superalloys, IN738LC has a good high-temperature strength and hot corrosion resistance. Coherency strains between the FCC gamma matrix (γ)- and L12 gamma prime (γ′)-precipitate phase particles mainly provide the high-temperature strength in IN738LC. Conical IN738LC specimens have been aged under compression for various times [24, 192, 480, and 960 hours at 1223 K (950 °C) and 12, 24, 192, and 480 hours at 1323 K (1050 °C)] in order to observe the morphological evolution of the γ′ precipitate microstructure. Dislocations play a determining role in morphological changes. Fingerprints of matrix dislocations in the form of indentations on γ′ precipitates have been identified by scanning electron microscope. Precipitate morphology has become more complex through dissolution/merging as temperature, aging time, and stress have increased. The precipitate morphology has evolved toward rafting at appropriate strain, temperature, and time. Localized slip bands have marked the beginning of rafting. The rafts have been observed at around a 45 deg angle away from the load direction. For higher stress positions, there is a trend toward N-type rafting which is expected of a positive misfit alloy under compression. Rafts eventually have collapsed due to severe creep deformation.

Keywords

Longitudinal Plane Lattice Misfit Coherency Strain Stress Position Precipitate Morphology 
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.

Notes

Acknowledgments

The authors acknowledge the financial support for this work by Bogazici University Scientific Research Projects (BAP) under Grant No. 08A601.

References

  1. 1.
    R.C. Reed: The Superalloys-Fundamentals and Applications, Cambridge University Press, New York, NY, 2006.CrossRefGoogle Scholar
  2. 2.
    T. Miyazaki, K. Nakamura, and H. Mori: J. Mater. Sci., 1979, vol. 14 (8), pp. 1827-37.CrossRefGoogle Scholar
  3. 3.
    C.T. Sims, N.S. Stoloff, and W.C. Hagel (editors): Superalloys IIHigh- Temperature Materials for Aerospace and Industrial Power, Wiley, New York, NY, 1987.Google Scholar
  4. 4.
    R.A Ricks, A.J. Porter, and R.C. Ecob: Acta Metall., 1983, vol. 31 (1), pp. 43-53.CrossRefGoogle Scholar
  5. 5.
    A. Hazotte and J. Lacaze: Scripta Metall., 1989, vol. 23, pp. 1877-82.CrossRefGoogle Scholar
  6. 6.
    S.V. Prikhodko and A.J. Ardell: Acta Mater., 2003, vol. 51 (17), pp. 5021-36.CrossRefGoogle Scholar
  7. 7.
    J. Svoboda and P. Lukáš: Acta Mater., 1996, vol. 44 (6), pp. 2557-65.CrossRefGoogle Scholar
  8. 8.
    M. Doi, Mater. Trans., 1992, vol. 33 (7), pp. 637-49.CrossRefGoogle Scholar
  9. 9.
    H. Mughrabi: Mater. Sci. Technol., 2009, vol. 25 (2), pp. 191-204.CrossRefGoogle Scholar
  10. 10.
    J. Chang and S.M. Allen: J. Mater. Res., 1991, vol. 6 (9), pp. 1843-55.CrossRefGoogle Scholar
  11. 11.
    A.F. Giamei, D.D. Pearson, and D.L. Anton: Mat. Res. Soc. Symp. Proc., 1985, vol. 39, pp. 293-308.CrossRefGoogle Scholar
  12. 12.
    J. Li and R.P. Wahi: Acta Metall. Mater., 1995, vol. 43 (2), pp. 507-17.CrossRefGoogle Scholar
  13. 13.
    T. Hino, T. Kobayashi, Y. Koizumi, H. Harada, and T. Yamagata: Superalloys 2000 (Ninth International Symposium), Champion, PA, The American Society for Metals, 2000, pp. 729–36.Google Scholar
  14. 14.
    M. Veron, Y. Bréchet, and F. Louchet: Acta Mater., 1996, vol. 44 (9), pp. 3633-41.CrossRefGoogle Scholar
  15. 15.
    S.G. Tian, C.R. Chen, J.H. Zhang, H.C. Yang, X. Wu, Y.B. Xu, and Z.Q. Hu: Mater. Sci. Technol., 2001, vol. 17 (6), pp. 736-44.Google Scholar
  16. 16.
    J.Y. Buffiere and M. Ignat: Acta Metall. Mater., 1995, vol. 43 (5), pp. 1791-97.CrossRefGoogle Scholar
  17. 17.
    W. Wu, Y. Guo, G. Dui, and Y. Wang: Comp. Mater. Sci., 2008, vol. 44 (2), pp. 259-64.CrossRefGoogle Scholar
  18. 18.
    S. Socrate and D. M. Parks: Acta Metall. Mater., 1993, vol. 41 (7), pp. 2185-2209.CrossRefGoogle Scholar
  19. 19.
    K. Tanaka, T. Ichitsubo, K. Kishida, H. Inui, and E. Matsubara: Acta Mater., 2008, vol. 56 (15), pp. 3786-90.CrossRefGoogle Scholar
  20. 20.
    A. Epishin, T. Link, and G. Nolze: J. Microsc., 2007, vol. 228, pp. 110–17.CrossRefGoogle Scholar
  21. 21.
    A. Bauer, S. Neumeier, F. Pyczak, R.F. Singer, and M. Goken: Mater. Sci. Eng. A, 2012, vol. 550, pp. 333-41.CrossRefGoogle Scholar
  22. 22.
    Y. Zhou, Z. Zhang, Z. H. Zhao, and Q. P. Zhong: Mater. Sci. Technol., 2012, vol. 28 (8), pp. 1018-21.CrossRefGoogle Scholar
  23. 23.
    N. Miura, K. Nakata, M. Miyazaki, Y. Hayashi, and Y. Kondo: Mater. Sci. Forum, 2010, vols. (638–642), pp. 2291–96.Google Scholar
  24. 24.
    F.Z. Sierra, D. Narzary, C. Bolaina, J.C. Han, J. Kubiak, and J. Nebradti: Heat Transfer and Thermal Mechanical Stress Distributions in Gas Turbine Blades, Presented at ASME Turbo Expo 2009: Power for Land, Sea, and Air, Orlando, FL, June 8–12, 2009.Google Scholar
  25. 25.
    A. Altincekic and E. Balikci: Metall. Mater. Trans. A, 2013, vol. 44A, pp. 2487-97.CrossRefGoogle Scholar
  26. 26.
    E. Balikci, R.A. Mirshams, and A. Raman: Z. Metallkd., 1999, vol. 90 (2), pp. 132-40.Google Scholar
  27. 27.
    The Nickel Producers Environmental Research Association (NIPERA): Alloy IN-738 Technical Data. http://www.nipera.org/~/Media/Files/TechnicalLiterature/IN_738Alloy_PreliminaryData_497_.pdf. Accessed Aug 2014.
  28. 28.
    E. Balikci: Ph.D. Dissertation, Louisiana State University, Baton Rouge, LA, 1998.Google Scholar
  29. 29.
    E. Balikci, R.A. Mirshams, and A. Raman: J. Mater. Eng. Perform., 2000, vol. 9 (3), pp. 324-29.CrossRefGoogle Scholar
  30. 30.
    A. Sato, J. Moverare, M. Hasselqvist, and R.C. Reed: Metall. Mater. Trans. A, 2012, vol. 43A, pp. 2302-15.CrossRefGoogle Scholar
  31. 31.
    J.J. Moverare, S. Johansson, and R.C. Reed: Acta Mater., 2009, vol. 57, pp. 2266-76.CrossRefGoogle Scholar
  32. 32.
    E. Balikci, R.A. Mirshams, and A. Raman: Metall. Mater. Trans. A, 1997, vol. 28A, pp. 1993–2003.CrossRefGoogle Scholar
  33. 33.
    J. Zrnik, P. Strunz, M. Maldini, A. Wiedenmann, and V. Davydov: J. Phys.-Condens. Mat., 2008, vol. 20 (10), pp. 104261-1–1-8.Google Scholar
  34. 34.
    H. Biermann, B. von Grossmann, T. Schneider, H. Feng, and H. Mughrabi: Superalloys 1996 (Eighth International Symposium), The American Society for Metals, Warrendale, PA, 1996, pp. 201–210.Google Scholar
  35. 35.
    A. Lasalmonie and J.L. Strudel: Philos. Mag., 1975, vol. 32 (5), pp. 937-49.CrossRefGoogle Scholar
  36. 36.
    P.J. Henderson and M. Mclean: Acta Metall., 1983, vol. 31 (8), pp. 1203-19.CrossRefGoogle Scholar
  37. 37.
    J.A. Carey, P.M. Sargent, and D.R.H Jones: J. Mater. Sci. Lett., 1990, vol. 9(5), pp. 572–75.Google Scholar
  38. 38.
    N. Matan, D.C. Cox, C.M.F. Rae, and R.C. Reed: Acta Mater., 1999, vol. 47 (7), pp. 2031-45.CrossRefGoogle Scholar
  39. 39.
    J.X. Yang, Q. Zheng, X.F.Sun, H.R. Guan, and Z.Q. Hu: Mater. Sci. Eng. A, 2007, vol. 457, pp. 148-55.CrossRefGoogle Scholar
  40. 40.
    O. Paris, M. Fahrmann, E. Fahrmann, T.M. Pollock, and P. Fratzl: Acta Mater., 1997, vol. 45 (3), pp. 1085-97.CrossRefGoogle Scholar
  41. 41.
    R.W. Hertzberg: Deformation and Fracture Mechanics of Engineering Materials, John Wiley & Sons, Inc., New York, NY, 1996.Google Scholar
  42. 42.
    R.C. Reed, D.C. Cox, and C.M.F. Rae: Mater. Sci. Eng. A, 2007, vol. 448, pp. 88-96.CrossRefGoogle Scholar
  43. 43.
    A. Epishin, T. Link, P. D. Portella, and U. Bruckner: Acta Mater., 2000, vol. 48, pp. 4169–77.CrossRefGoogle Scholar

Copyright information

© The Minerals, Metals & Materials Society and ASM International 2014

Authors and Affiliations

  1. 1.Department of Mechanical EngineeringBogazici UniversityBebekTurkey

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