Advertisement

Oxidation of Metals

, Volume 29, Issue 3–4, pp 289–306 | Cite as

Carbon transport through oxide scales on Fe-Cr alloys

  • I. Wolf
  • H. J. Grabke
  • P. Schmidt
Article

Abstract

The penetration of carbon through Cr2O3 layers was studied for a series of different Fe-Cr alloys using a radioactive tracer method. Preoxidized samples were exposed at 900°C for 700 hr in a H2 -H2O -CO-CO2 atmosphere tagged with14C; carbon penetration profiles were then determined, and the lateral distribution of carbon was observed by autoradiography. Even minute amounts of carbon (⩾0.05 ppm) within the scale and in the alloy could be detected. The carbon uptake into different Fe-Cr alloys decreased with increasing Cr content to a minimum for the alloys with 12.5–20% Cr, indicating low porosity and good adherence of the Cr2O3 layers. Poor scale adherence was observed for Fe-10% Cr but could be improved by Ce additions. Porosity increased with contents >20% Cr of the alloys. Pore formation could be induced by impurities, e.g., SiC particles distributed on the surface.

Key words

Preoxidation Cr2O3 formation carburization scale porosity 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    H. J. Grabke, inAufbau von Oxidschichten auf Hochtemperaturwerkstoffen und ihre technische Bedeutung, A. Rahmel, ed. Deutsche Gesellschaft für Metallkunde, 1983, p. 89.Google Scholar
  2. 2.
    A. Schnaas and H. J. Grabke,Oxid. Met. 12, 387 (1978).Google Scholar
  3. 3.
    H. J. Grabke and A. Schnaas,Proceedings of the Petten Conference (North-Holland, Amsterdam, 1978), p. 195.Google Scholar
  4. 4.
    H. J. Grabke, K. Ohla, J. Peters, and I. Wolf,Werkst. Korros. 34, 49 (1983).Google Scholar
  5. 5.
    I. Wolf and H. J. Grabke,Solid State Commun. 54, 5 (1985).Google Scholar
  6. 6.
    T. N. Rhys-Jones and H. J. Grabke,Corros. Sci. 27, 49 (1987).Google Scholar
  7. 7.
    T. N. Rhys-Jones and H. J. Grabke,Werkst. Korros. 36, 65 (1987).Google Scholar
  8. 8.
    I. Wolf and H. J. Grabke,Proceedings of the Eight Congress European Corrosion, Nice, Vol. 1 (1985) p. 48.Google Scholar
  9. 9.
    J. A. Colwell and R. A. Rapp,Metall. Trans. 17A, 1065 (1986).Google Scholar
  10. 10.
    K. Bungardt, H. Preisendanz, and G. Lehnert,Arch. Eisenhuettenwes. 35, 999 (1964).Google Scholar
  11. 11.
    C. Wagner,J. Electrochem. Soc. 103, 571 (1956).Google Scholar
  12. 12.
    International Workshop on Critical Issues Concerning the Mechanisms of High-Temperature Corrosion, A Rahmel, G. C. Wood, P. Kofstad, and D. L. Douglass, eds.,Oxid. Met. 23, 251 (1985).Google Scholar
  13. 13.
    S. Mrowec, inProceedings of the Third JIM Insternational Symposium on High Temperature Corrosion of Metals and Alloys, Japan (Nov. 1982).Google Scholar
  14. 14.
    D. Bramhoff, H. J. Grabke, and P. Schmidt,Corros. Sci. (in press).Google Scholar
  15. 15.
    A. Atkinson and R. Taylor, AERE report R11314, Harwell (1984).Google Scholar
  16. 16.
    D. F. Mitchell, R. J. Hussey, and M. J. Graham,J. Vac. Sci. Technol. A1, 1006 (1983).Google Scholar

Copyright information

© Plenum Publishing Corporation 1988

Authors and Affiliations

  • I. Wolf
    • 1
  • H. J. Grabke
    • 2
  • P. Schmidt
    • 2
  1. 1.Institut für Nuklear FestkörperphysikKernforschungszentrum KarlsruheFederal Republic of Germany
  2. 2.Max-Planck-Institut für Eisenforschung GmbHDüsseldorfFederal Republic of Germany

Personalised recommendations