Advertisement

Microstructure of Bare and Sol–Gel Alumina-Coated Nickel-Base Alloy Inconel 625 After Long-Term Oxidation at 900 °C

  • M. NofzEmail author
  • I. Dörfel
  • R. Sojref
  • R. Saliwan Neumann
Original Paper
  • 31 Downloads

Abstract

Though Ni-based superalloys show a high oxidation and corrosion resistance, coatings can still improve these properties, especially if used at temperatures up to 1000 °C. Here, a coating was prepared by applying a boehmite-sol via dip-coating and a subsequent heat treatment at 600 °C for 30 min. To evaluate the coating, the oxidation behavior of bare and alumina-coated Ni-base alloy Inconel 625 in air at 900 °C was studied for up to 2000 h. Electron microscopy studies of sample surfaces and cross sections showed that (1) in the 3.5–6.3 µm-thick scale formed on the bare alloy, Fe and Ni are located as fine precipitates at the grain boundaries of the chromia-rich scale, (2) Ni and Ti are concentrated to a minor degree at the grain boundaries of the scale, too; and for the coated sample: (3) the only 1.8-µm-thick sol–gel alumina coating slows down the formation of chromia on the alloy surface and reduces the outward diffusion of the alloy constituents. The protective effect of the coating was evidenced by (1) diminished chromium diffusion at grain boundaries resulting in less pronounced string-like protrusions at the outer surface of the coated IN 625, (2) formation of a Cr-enriched zone above the alloy surface which was thinner than the scale on the uncoated sample, (3) lower extension in depth of Cr depletion in the superficial zone of the alloy surface of the coated sample in comparison with that region of the uncoated one, and (4) a narrower zone of formation of Kirkendall pores.

Graphical Abstract

Keywords

Inconel 625 High-temperature oxidation Oxidation protection Sol–gel coating 

Notes

Acknowledgements

The authors wish to thank Axel Kranzmann for helpful discussions and hints.

References

  1. 1.
    C. H. White, in The Development of Gas Turbine Materials, ed. G. W. Meetham (Springer, Dordrecht, 1981), p. 89.CrossRefGoogle Scholar
  2. 2.
    D. Seo, M. Sayar, and K. Ogawa, Surface & Coatings Technology 206, 2851 (2012).CrossRefGoogle Scholar
  3. 3.
    J. Liu, D. Dyson, and E. Asselin, Oxidation of Metals 86, 135 (2016).CrossRefGoogle Scholar
  4. 4.
    D. M. Gorman, R. L. Higginson, H. Du, G. McColvin, A. T. Fry, and R. C. Thomson, Oxidation of Metals 79, 553 (2013).CrossRefGoogle Scholar
  5. 5.
    D. Fantozzi, V. Matikainen, M. Uusitalo, H. Koivuluoto, and P. Vuoristo, Surface & Coatings Technology 318, 233 (2017).CrossRefGoogle Scholar
  6. 6.
    T. Sugama, Journal of Sol-Gel Science and Technology 12, 35 (1998).CrossRefGoogle Scholar
  7. 7.
    T. Sugama, Surface and Coatings Technology 106, 106 (1998).CrossRefGoogle Scholar
  8. 8.
    H. Cho, D. M. Lee, J. H. Lee, K. H. Bang, and B. W. Lee, Surface & Coatings Technology 202, 5625 (2008).CrossRefGoogle Scholar
  9. 9.
    M. Dressler, M. Nofz, R. Saliwan-Neumann, I. Dörfel, and M. Griepentrog, Thin Solid Films 517, 786 (2008).CrossRefGoogle Scholar
  10. 10.
    M. Dressler, M. Nofz, I. Dörfel, and R. Saliwan-Neumann, Surface & Coatings Technology 202, 6095 (2008).CrossRefGoogle Scholar
  11. 11.
    M. Nofz, I. Dörfel, R. Sojref, N. Wollschläger, M. Mosquera-Feijoo, and A. Kranzmann, Journal of Sol-Gel Science and Technology 81, 185 (2017).CrossRefGoogle Scholar
  12. 12.
    M. Nofz, I. Dörfel, R. Sojref, et al., Oxidation of Metals 89, 453 (2018).CrossRefGoogle Scholar
  13. 13.
    www.specialmetals.com; downloaded 14 June 2018.
  14. 14.
    L. Kumar, R. Venkataramani, M. Sundararaman, P. Mukhopadhyay, and S. P. Garg, Oxidation of Metals 45, 221 (1996).CrossRefGoogle Scholar
  15. 15.
    A. Chyrkin, Oxidation of Metals 75, 143 (2011).CrossRefGoogle Scholar
  16. 16.
    E. N’dah, M. P. Hierro, K. Borrero, and F. J. Pérez, Oxidation of Metals 68, 9 (2007).CrossRefGoogle Scholar
  17. 17.
    J. Zurek, D. J. Young, E. Essuman, et al., Materials Science and Engineering A 477, 259 (2008).CrossRefGoogle Scholar
  18. 18.
    M. D. Mathew, P. Paraweswaran, and K. Bhanu Sankara Rao, Materials Characterization 59, 508 (2008).CrossRefGoogle Scholar
  19. 19.
    P. Petrzak, K. Kowalski, and M. Blicharski, Acta Physica Polonica A 130, 1041 (2016).CrossRefGoogle Scholar
  20. 20.
    R. P. Oleksak, C. S. Carney, G. R. Holcomb, and Ö. N. Doğan, Oxidation of Metals 90, 27 (2018).CrossRefGoogle Scholar
  21. 21.
    M. Abbasi, D.-I. Kim, J.-H. Shim, and W.-S. Jung, Journal of Alloys and Compounds 658, 210 (2016).CrossRefGoogle Scholar
  22. 22.
    K. H. A. Al-Hatab, M. A. Al-Bukhaiti, U. Krupp, and M. Kantehm, Oxidation of Metals 75, 209 (2011).CrossRefGoogle Scholar
  23. 23.
    D. M. England and A. V. Virkar, Journal of the Electrochemical Society 146, 3196 (1999).CrossRefGoogle Scholar
  24. 24.
    J.-H. Kim, B. K. Kim, D. I. Kim, P. P. Choi, D. Raabe, and K. W. Yi, Corrosion Science 96, 52 (2015).CrossRefGoogle Scholar
  25. 25.
    C. Ostwald and H. J. Grabke, Corrosion Science 46, 1113 (2004).CrossRefGoogle Scholar
  26. 26.
    A. C. S. Sabioni, A. M. Huntz, L. C. Borges, and F. Jomard, Philosophical Magazine 87, 1921 (2007).CrossRefGoogle Scholar
  27. 27.
    A. C. S. Sabioni, A. M. Huntz, F. Silva, and F. Jomard, Materials Science and Engineering A 392, 254 (2005).CrossRefGoogle Scholar
  28. 28.
    A. C. S. Sabioni, A. M. Huntz, J. N. V. Souza, F. Jomard, and M. D. Martins, Philosophical Magazine 88, 391 (2008).CrossRefGoogle Scholar
  29. 29.
    D. Kim, C. Jang, and W. S. Ryu, Oxidation of Metals 71, 271 (2009).CrossRefGoogle Scholar
  30. 30.
    D. L. Douglass and J. S. Armijo, Oxidation of Metals 2, 207 (1970).CrossRefGoogle Scholar
  31. 31.
    A. Ul-Hamid, Anti-Corrosion Methods and Materials 51, 216 (2004).CrossRefGoogle Scholar
  32. 32.
    S. Pedrazzini, E. S. Kiseeva, R. Escoube, et al., Oxidation of Metals 89, 375 (2018).CrossRefGoogle Scholar
  33. 33.
    J. Litz, A. Rahmel, M. Schorr, and J. Weiss, Oxidation of Metals 32, 167–184 (1989).CrossRefGoogle Scholar
  34. 34.
    E. Schmucker, C. Petitjean, L. Martinelli, P. J. Panteix, S. Ben Lagha, and M. Vilasi, Corrosion Science 111, 474 (2016).CrossRefGoogle Scholar
  35. 35.
    T. Connolley, P. A. S. Reed, and M. J. Starink, Materials Science and Engineering A 340, 139 (2003).CrossRefGoogle Scholar
  36. 36.
    H. Nakajima, JOM The Journal of the Minerals, Metals & Materials Series (TMS) 49, 15 (1997).CrossRefGoogle Scholar
  37. 37.
    E. Schmucker, C. Petitjean, L. Martinelli, P.-J. Panteix, B. Lagha, and M. Vilasi, Corrosion Science 111, 467 (2016).CrossRefGoogle Scholar
  38. 38.
    B. Jönsson and A. Westerlund, Oxidation of Metals 88, 315 (2017).CrossRefGoogle Scholar
  39. 39.
    D. Kim, D. Kim, H. J. Lee, C. Jang, and D. J. Yoon, Journal of Nuclear Materials 441, 612 (2013).CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Federal Institute for Materials Research and TestingBerlinGermany

Personalised recommendations