Advertisement

Metallurgical Transactions A

, Volume 23, Issue 6, pp 1617–1626 | Cite as

Observation of {011} twins in Fe−Ni−C martensite using neutron powder diffraction

  • B. D. Butler
  • J. B. Cohen
Transformations

Abstract

High resolution neutron powder diffraction measurements were performed on freshly quenched specimens of Fe-13 wt pct Ni-1.0 wt pct C martensite formed at subambient temperature and after aging for 1 hour to 293, 313, 333 and 353 K. The widths of the powder reflections in the unaged martensite indicate the presence of a large number of {011} twins in this tetragonal structure. The {011} twins were modeled as single layer randomly distributed twin faults. The model predicts powder peak breadths with the unmistakable reflection index dependence that is observed in the measured powder spectra. The magnitude of the observed peak broadening is consistent with a twin volume of 17(±4) pct. Upon aging, there is no detectable change in the number of {011} twins despite an observed decrease in the tetragonality. Previous transmission electron microscope (TEM) measurements have demonstrated the presence of these twins, but it was not clear if they formed during the martensitic transformation or upon warming from subambient temperature. This study confirms their presence immediately after transformation, indicating that they may play an important role in the transformation.

Keywords

Austenite Martensite Metallurgical Transaction Fault Plane Fault Probability 
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.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    A.L. Roytburd and A.G. Khachaturyan:Phys. Met. Metallogr., 1970, vol. 30 (6), pp. 68–77.Google Scholar
  2. 2.
    G.V. Kurdjumov and A.G. Khachaturyan:Acta Metall., 1975, vol. 23, pp. 1077–88.CrossRefGoogle Scholar
  3. 3.
    V.I. Izotov and L.M. Utevskiy:Phys. Met. Metallogr., 1968, vol. 25 (1), pp. 86–96.Google Scholar
  4. 4.
    M. Oka and C.M. Wayman:Trans. AIME, 1968, vol. 242, pp. 337–38.Google Scholar
  5. 5.
    M. Oka and C.M. Wayman:Trans. ASM, 1969, vol. 62, pp. 370–79.Google Scholar
  6. 6.
    K.A. Taylor, G.B. Olson, M. Cohen, and J.B. Vander Sande:Metall. Trans. A, 1989, vol. 20A, pp. 2739–47.Google Scholar
  7. 7.
    V. Ye. Danil’chenko:Phys. Met. Metallogr., 1987, vol. 64 (4), pp. 110–14.Google Scholar
  8. 8.
    B.E. Warren:X-ray Diffraction, 1969, Addison-Wesley, Reading, MA.Google Scholar
  9. 9.
    L.H. Schwartz and J.B. Cohen:Diffraction from Materials, 1987, Springer-Verlag, Berlin.Google Scholar
  10. 10.
    S.E. Hartfield: M.S. Thesis, Massachusetts Institute of Technology, Cambridge, MA, 1988.Google Scholar
  11. 11.
    C.J.N. Wagner: inLocal Atomic Arrangements Studied by X-ray Diffraction, J.B. Cohen and J.E. Hilliard, eds., Gordon and Breach, New York, NY, 1966.Google Scholar
  12. 12.
    I.R. Entin, V.A. Somenkov, and S. Sh. Shil’shtein:Sov. Phys. Dokl., 1973, vol. 17 (10), pp. 1021–23.Google Scholar
  13. 13.
    G.B. Olson and M. Cohen:Metall. Trans. A, 1983, vol. 14A, pp. 1057–65.Google Scholar
  14. 14.
    P.C. Chen and P.G. Winchell:Metall. Trans. A, 1980, vol. 11A, pp. 1333–39.Google Scholar
  15. 15.
    A.G. Khachaturyan, S.M. Shapiro, and S. Semenovskaya:Phys. Rev. B, vol. 43 (13), pp. 10832–843.Google Scholar
  16. 16.
    A. Guinier:X-ray Diffraction in Crystals, Imperfect Crystals, and Amorphous Bodies, W.H. Freeman and Co., San Francisco, CA, 1963.Google Scholar

Copyright information

© The Minerals, Metals & Materials Society and ASM International 1992

Authors and Affiliations

  • B. D. Butler
  • J. B. Cohen
    • 1
  1. 1.McCormick School of EngineeringNorthwestern UniversityEvanston

Personalised recommendations