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Neutron diffraction study of austempered ductile iron

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Abstract

Crystallographic properties of an austempered ductile iron (ADI) were studied by using neutron diffraction. A quantitative phase analysis based on Rietveld refinements revealed three component phases, α-Fe (ferrite), γ-Fe (austenite), and graphite precipitate, with weight fractions of 66.0, 31.5, and 2.5 pct, respectively. The ferrite phases of the samples were found to be tetragonal,14/mmm, with ac/a ratio of about 0.993, which is very close to the body-centered cubic (bcc) structure. The austenite phase had C atoms occupying the octahedral site of the face-centered cubic (fcc) unit cell with about 8 pct occupancy ratio. A strong microstrain broadening was observed for the two Fe phases of the samples. The particle sizes of the acicular ferrite phase were studied by using small angle neutron scattering. The analysis suggested a mean rod diameter of 700 A. The scattering invariant predicts a ferrite volume fraction consistent with the powder diffraction analysis. A textbook case of nodular graphite segregation, with average diameters ranging from 10 to 20 μm, was observed by optical micrography.

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References

  1. J.R. Laub:Adv. Mater. Processes, 1994, vol. 145, pp. 40–43.

    Google Scholar 

  2. C.S. Choi, E.F. Baker, and J. Orosz: inAdvances in X-ray Analysis, J.V. Gilfrich, C.C. Goldsmith, T.C. Huang, R. Jenkins, I.C. Noyan, D.K. Smith, and P.K. Predicki, eds., Plenum Press, New York, NY, 1994, vol. 37, pp. 49–57.

    Google Scholar 

  3. H.M. Rietveld:J. Appl. Cryst., 1969, vol. 2, pp. 65–71.

    Article  CAS  Google Scholar 

  4. R. Delhez, T.H. de Keijsey, J.I. Langford, D. Louer, E.J. Mittemeijer, and E.J. Sonneveld: inThe Rietveld Method, Y.A. Young, ed., Oxford University Press, Oxford, United Kingdom, 1993, ch. 8.

    Google Scholar 

  5. H.P. Klug and L.E. Alexander:X-ray Diffraction Procedures for Polycrystalline and Amorphous Materials, 2nd ed., Wiley, New York, NY, 1974.

    Google Scholar 

  6. P. Scherrer:Gottinger Nachrichten, 1918, vol. 2, pp. 98–103.

    Google Scholar 

  7. R.J. Hill and C.J. Howard:J. Appl. Cryst., 1987, vol. 20, pp. 467–74.

    Article  CAS  Google Scholar 

  8. G. Caglioti, A. Paoletti, and F.P. Ricci:Nucl. Instrum. Methods, 1958, vol. 3, pp. 223–28.

    Article  CAS  Google Scholar 

  9. R.J. Wallace:Encyclopedia of Materials Science and Engineering, Pergamon Press, Oxford, United Kingdom, 1986, pp. 743–46.

    Google Scholar 

  10. Annual Book of ASTM Standards, ASTM Designation A897M-90, ASTM, Philadelphia, PA, 1995, vol. 01.02.

  11. C.S. Choi and H.J. Prask:J. Appl. Cryst., 1985, pp. 141-44.

  12. J. Rodriguez-Carvajal: Program FULLPROF, Version 2.5, Institut Laue-Langevin, Grenoble, France, 1994.

    Google Scholar 

  13. A. Guinier:Ann. Phys., 1939, vol. 12, p. 161.

    CAS  Google Scholar 

  14. G. Porod: inSmall-Angle Xray Scattering, O. Glatter and O. Kratky, eds., Academic Press, London, 1982, pp. 17–51.

    Google Scholar 

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Authors and Affiliations

  1. Armament Research Development and Engineering Center, United States Army, 07806, Picatinny Arsenal, NJ

    C. S. Choi (Research Physicist) & W. Sharpe (Materials Engineer)

  2. Materials Science and Engineering Laboratory, National Institute of Standards and Technology, 20899, Gaithersburg, MD

    J. Barker (Materials Engineer) & R. J. Fields (Metallurgist)

Authors
  1. C. S. Choi
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  2. W. Sharpe
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  3. J. Barker
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  4. R. J. Fields
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Choi, C.S., Sharpe, W., Barker, J. et al. Neutron diffraction study of austempered ductile iron. Metall Mater Trans A 27, 923–928 (1996). https://doi.org/10.1007/BF02649759

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  • DOI: https://doi.org/10.1007/BF02649759

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