Skip to main content
Log in

The role of manganese and copper in the eutectoid transformation of spheroidal graphite cast iron

  • Published:
Metallurgical and Materials Transactions A Aims and scope Submit manuscript

Abstract

The decomposition of austenite to ferrite plus graphite or to pearlite in spheroidal graphite (SG) cast iron is known to depend on a number of factors among which are the nodule count, the cooling rate, and the alloying additions (Si, Mn, Cu, etc.). This study was undertaken in order to deepen the understanding of the effect of alloying with Mn and/or Cu on the eutectoid reaction. For this purpose, differential thermal analyses (DTAs) were carried out in which samples were subjected to a short homogenization treatment designed to smooth out the microsegregations originating from the solidification step. The effect of various additions of copper and manganese and of the cooling rate on the temperature of the onset of the stable and metastable eutectoid reactions was investigated. A description of the conditions for the growth of ferrite and of pearlite is given and shows that these reactions can develop only when the temperature of the alloy is below the lower boundary of the ferrite/austenite/graphite or ferrite/austenite/cementite related three-phase field. The experimental results can be explained if the appropriate reference temperature is used. The cooling rate affects the temperature of the onset of the ferrite plus graphite growth in the same way as for the eutectic reaction, with a measured undercooling that can be extrapolated to a zero value when the cooling rate is zero. The growth undercooling of pearlite had values that were in agreement with similar data obtained on silicon steels. The detrimental effect of Mn on the growth kinetics of ferrite during the decomposition of austenite in the stable system is explained in terms of the driving force for diffusion of carbon through the ferrite ring around the graphite nodules. Finally, it is found that copper can have a pearlite promoter role only when combined with a low addition of manganese.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  1. K.E. Spray: Metals Handbook, ASM, Metals Park, OH, 1981, vol. 4, pp. 545–51.

    Google Scholar 

  2. W.C. Johnson and B.V. Kovacs: Metall. Trans. A, 1978, vol. 9A, pp. 219–29.

    CAS  Google Scholar 

  3. D. Venugopalan: in Fundamental and Applications of Ternary Diffusion, G.R., Purdy ed., Pergamon Press, New York, NY, 1990, pp. 173–83.

    Google Scholar 

  4. E.N. Pan, M.S. Lou, and C.R. Loper: AFS Trans., 1979, vol. 87, pp. 819–40.

    Google Scholar 

  5. M.J. Lalich and C.R. Loper: AFS Trans., 1973, vol. 81, pp. 217–28.

    CAS  Google Scholar 

  6. D.R. Askeland and S.S. Gupta: AFS Trans., 1975, vol. 83, pp. 313–20.

    Google Scholar 

  7. J. Lacaze, S. Ford, C. Wilson, and E. Dubu: Scand. J. Metall., 1993, vol. 22, pp. 300–309.

    CAS  Google Scholar 

  8. B.V. Kovacs: AFS Trans., 1981, vol. 89, pp. 79–96.

    CAS  Google Scholar 

  9. J. Ågren: Acta Metall., 1982, vol. 30, pp. 841–51.

    Article  Google Scholar 

  10. J. Lacaze, C. Wilson, and C. Bak: Scand. J. Metall., 1994, vol. 23, pp. 151–63.

    CAS  Google Scholar 

  11. U. Ekpoom and R.W. Heine: AFS Trans., 1978, vol. 86, pp. 281–86.

    CAS  Google Scholar 

  12. J. Ågren: Scand. J. Metall., 1982, vol. 11, pp. 3–8.

    Google Scholar 

  13. E.E. Underwood: Quantitative Stereology, Addison-Wesley, Reading, MA, 1970.

    Google Scholar 

  14. J.M. Theret and J.C. Lecomte: in Quantitative Analysis of Microstructures in Materials, Science, Biology and Medicine, J.L. Chermant, ed., Dr. Riederer Verlag GmbH, Stuttgart, 1978, pp. 153–60.

    Google Scholar 

  15. T. Skaland and O. Grong: AFS Trans., 1991, vol. 99, pp. 153–57.

    CAS  Google Scholar 

  16. E.A. Feest, G. McHugh, D.O. Morton, L.S. Welch, and I.A. Cook: Solidification Technology in the Foundry and Casthouse, The Metals Society, London, 1983, pp. 232–39.

    Google Scholar 

  17. J. Lacaze and G. Lesoult: in Nature and Properties of Semi-Solid Materials, and J.A. Sekhar and J.A. Dantzig, eds., TMS, Warrendale, PA, 1991, pp. 105–42.

    Google Scholar 

  18. B.F. Brown and M.E. Hawkes: AFS Trans., 1951, vol. 59, pp. 181–200.

    Google Scholar 

  19. B. Sundman, B. Jansson, and J.-O. Andersson: CALPHAD, 1985, vol. 9, pp. 153–90.

    Article  CAS  Google Scholar 

  20. B. Uhrenius: Hardenability Concepts with Applications to Steel, TMS-AIME, Warrendale, PA, 1977, pp. 28–81.

    Google Scholar 

  21. J. Lacaze, M. Castro, N. Aichoun, and G. Lesoult: Mem. Et. Scient. Rev. Met., 1989, pp. 85–97.

  22. S.A. Al-Salman, G.W. Lorimer, and N. Ridley: Acta Metall., 1979, vol. 27, pp. 1391–1400.

    Article  CAS  Google Scholar 

  23. S.K. Tewari and R.C. Sharma: Metall. Trans. A, 1985, vol. 16A, pp. 597–603.

    CAS  Google Scholar 

  24. M. Hillert: in Mechanism of Phase Transformation in Crystalline Solids, Monograph No. 33, The Institute of Metals, London, 1968, pp. 231–47.

    Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Rights and permissions

Reprints and permissions

About this article

Cite this article

Boudot, A., Gerval, V., Oquab, D. et al. The role of manganese and copper in the eutectoid transformation of spheroidal graphite cast iron. Metall Mater Trans A 28, 2015–2025 (1997). https://doi.org/10.1007/s11661-997-0158-7

Download citation

  • Received:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s11661-997-0158-7

Keywords

Navigation