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Mechanical properties of 0.40 pct C-Ni-Cr-Mo high strength steel having a mixed structure of martensite and bainite

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Abstract

A study has been systematically made of the effect of bainite on the mechanical properties of a commercial Japanese 0.40 pct C-Ni-Cr-Mo high strength steel (AISI 4340 type) having a mixed structure of martensite and bainite. Isothermal transformation of lower bainite at 593 K, which appeared in acicular form and partitioned prior austenite grains, in association with tempered marprovided provided a better combination of strength and fracture ductility, improving true notch tensile strength (TNTS) and fracture appearance transition temperature (FATT) in Charpy impact tests. This occurred regardless of the volume fraction of lower bainite present and/or the tempering conditions employed to create a difference in strength between the two phases. Upper bainite which was isothermally transformed at 673 K appeared as masses that filled prior austenite grains and had a very detrimental effect on the strength and fracture ductility of the steel. Significant damage occurred to TNTS and FATT, irrespective of the volume fraction of upper bainite present and/or the tempering conditions employed when the upper bainite was associated with tempered martensite. However, when the above two types of bainite appeared in the same size, shape, and distribution within tempered martensite approximately equalized to the strength of the bainite, a similar trend or a marked similarity was observed between the tensile properties of the mixed structures and the volume fraction of bainite. From the above results, it is assumed that the mechanical properties of high strength steels having a mixed structure of martensite and bainite are affected more strongly by the size, shape, and distribution of bainite within martensite than by the difference in strength between martensite and bainite or by the type of mixed bainite present. The remarkable effects of the size, shape, and distribution of bainite within martensite on the mechanical properties of the steel are briefly discussed in terms of the modified law of mixtures, metallographic examinations, and the analyses of stress-strain diagrams.

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References

  1. R. F. Hehemann, V. J. Luhan, and A. R. Troiano:Trans. ASM, 1957, vol. 49, pp. 409–26.

    Google Scholar 

  2. D. P. Edwards:JISl, 1969, vol. 207, pp. 1494–502.

    CAS  Google Scholar 

  3. R.J. Kar, R.M. Horn, and V.F. Zackey:Metall. Trans. A, 1979, vol. 10A, pp. 1711–17.

    CAS  Google Scholar 

  4. Y. Tomita and K. Okabayashi:ibid., 1983, vol. 14A, pp. 485–92.

    Google Scholar 

  5. E.F. Bailey:Trans. ASM, 1954, vol. 46, pp. 830–50.

    Google Scholar 

  6. K. Okabayashi, Y. Tomita, and I. Kuroki:Tetsu-to-Hagané, 1976, vol. 62, pp. 661–69.

    CAS  Google Scholar 

  7. Y. Tomita, S. Oki, and K. Okabayashi:ibid., 1978, vol. 64, pp. 78–87.

    Google Scholar 

  8. Y. Tomita, K. Miyamoto, and K. Okabayashi:ibid., 1978, vol. 64, pp. 759–68.

    CAS  Google Scholar 

  9. D.H. Huang and G. Thomas:Metall. Trans., 1971, vol. 2, pp. 1587–98.

    CAS  Google Scholar 

  10. G.E. Dieter:Ductility, H. W. Paxton, ed., ASM, Metals Park, OH, 1968, pp. 1–30.

    Google Scholar 

  11. J.E. Hilliard and J.W. Cahn:Trans. AIME, 1961, vol. 221, pp. 344–52.

    CAS  Google Scholar 

  12. C. A. Clark and P. M. Munro:JISI, 1962, vol. 200, pp. 395–98.

    CAS  Google Scholar 

  13. A. J. Baker, P.M. Kelly, and J. Nutting:Electron Microscopy and Strength of Crystals, G. Thomas and J. Washburn, eds., Interscience Publishers, a division of John Wiley & Sons, New York, London, 1963, pp. 899–916.

    Google Scholar 

  14. W. L. Grube:Rev. Universelle Mines, 1956, vol. 12, pp. 526–36.

    Google Scholar 

  15. S. Mates and R. F. Hehemann:Trans. AIME, 1961, vol. 221, pp. 179–85.

    Google Scholar 

  16. H.K.D.H. Bhadeshia:Acta Metall., 1980, vol. 28, pp. 1103–14.

    Article  CAS  Google Scholar 

  17. A.B. Greninger and A.R. Troiano:Trans. ASM, 1940, vol. 28, pp. 537–74.

    CAS  Google Scholar 

  18. M. J. Roberts:Metall. Trans., 1970, vol. 1, pp. 3287–94.

    CAS  Google Scholar 

  19. T. Swarr and G. Krauss:Metall. Trans. A, 1976, vol. 7A, pp. 41–48.

    CAS  Google Scholar 

  20. L.-Å. Norström:Scand. J. Metall., 1976, vol. 5, pp. 41–48.

    Google Scholar 

  21. N. Bredzs:Welding J., 1954, vol. 35, pp. 545–63?s.

    Google Scholar 

  22. G. Hansel:ibid., 1956, vol. 35, pp. 211–16?s.

    Google Scholar 

  23. R.L. Peaslee:ibid., 1976, vol. 55, pp. 850–58.

    CAS  Google Scholar 

  24. Y. Tomita, S. Oki, and K. Okabayashi:Tetsu-to-Hagané, 1978, vol. 64, pp. 459–68.

    Google Scholar 

  25. M.E. Morton:Austral. Inst. Metal, 1911, vol. 22, pp. 86–98.

    Google Scholar 

  26. R.E. Reed-Hill, W.R. Cribb, and S.N. Monteiro:Metall. Trans., 1973, vol. 4, pp. 2665–67.

    CAS  Google Scholar 

  27. W. Truszkowski:Mem. Sci. Rev. Metallurge., 1980, vol. 77, pp. 193–201.

    CAS  Google Scholar 

  28. Y. Tomita and K. Okabayashi:Metall. Trans. A, 1985, vol. 16A, p. 83.

    CAS  Google Scholar 

  29. J. H. Hollomon:Trans. AIME, 1945, vol. 162, pp. 268–90.

    Google Scholar 

  30. D.V. Wilson and Y. A. Konnan:Acta Metall., 1964, vol. 12, pp. 617–28.

    Article  CAS  Google Scholar 

  31. M.F. Ashby:Phil. Mag., 1970, vol. 21, pp. 399–424.

    CAS  Google Scholar 

  32. J.T. Barnby:Acta Metall., 1967, vol. 15, pp. 903–09.

    Article  CAS  Google Scholar 

  33. E. Smith and J.T. Barnly:Metal sci. J., 1967, vol. 1, pp. 1–4.

    Article  CAS  Google Scholar 

  34. E. Smith:Inst. J. Fract. Mech., 1968, vol. 4-2, pp. 131–45.

    Google Scholar 

  35. A.R. Rosenfield, E. Votava, and G.T. Hahn:Trans. ASM, 1968, vol. 61, pp. 807–15,

    Google Scholar 

  36. G. Oates:JISI, 1969, vol. 207, pp. 353–57.

    CAS  Google Scholar 

  37. T.C. Lindley, G. Oates, and C.E. Richards:Acta Metall., 1970, vol. 18, pp. 1127–36.

    Article  CAS  Google Scholar 

  38. T.M.F. Ronald:Metall. Trans., 1970, vol. 1, pp. 2583–92.

    Google Scholar 

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Authors and Affiliations

  1. Department of Metallurgical Engineering, College of Engineering, University of Osaka Prefecture, 4-804 Mozu-Umemachi, Sakai, 591, Osaka, Japan

    Yoshiyuki Tomita & Kunio Okabayashi

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  1. Yoshiyuki Tomita
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  2. Kunio Okabayashi
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Tomita, Y., Okabayashi, K. Mechanical properties of 0.40 pct C-Ni-Cr-Mo high strength steel having a mixed structure of martensite and bainite. Metall Trans A 16, 73–82 (1985). https://doi.org/10.1007/BF02656714

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  • DOI: https://doi.org/10.1007/BF02656714

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