Skip to main content
Log in

Strength and toughness of Fe-10ni alloys containing C, Cr, Mo, and Co

  • Published:
Metallurgical Transactions Aims and scope Submit manuscript

Abstract

The effects of C (0.10 to 0.20 pct), Cr (0 to 3 pct), Mo (0 to 2 pct), and Co (0 to 8 pct) on the yield strength, toughness (Charpy shelf energy), and tempering behavior of martensitic lONiCr-Mo-Co steels have been investigated. Variations in the carbon content between 0.10 and 0.20 pct result in yield strengths between 160 and 210 ksi (1.1 and 1.45 GN/m2) when these steels are tempered at 900° to 1000°F (480° to 540°C) for times of 1 to 100 h. These steels exhibit a secondary-hardening peak at 900° to 1000° F (480° to 540°C) where coarse Fe3C carbides are gradually replaced by a fine, dislocation-nucleated dispersion of (Mo, Cr)2C carbides. Maximum toughness at a given yield strength in these steels is only obtained when they are tempered for sufficiently long times so that the coarse Fe3C carbides are completely dissolved. Molybdenum is primarily responsible for the secondary-hardening peak observed in these steels. However, chromium additions do result in lower secondaryhardening temperatures and promote coarsening of the secondary-hardening carbide. Best combinations of strength and toughness are obtained with steels containing 2 pct Cr and 1 pct Mo. Cobalt increases the yield strength of these steels over the entire tempering range and results in a higher secondary-hardening peak. This effect of cobalt is attributed to 1) a retardation in the rate of recovery of the dislocation substructure of the martensite, 2) the formation of a finer dispersion of secondary-hardening carbides, and 3) solid-solution strengthening. The finer dispersion of secondary-hardening carbides in steels containing cobalt is favored by the finer dislocation substructure in these steels since the (Mo, Cr)2C carbide is dislocation-nucleated. This fine dispersion of (Mo, Cr)2C carbide combined with the high nickel content accounts for the excellent combination of strength and toughness exhibited by these steels.

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.

Institutional subscriptions

Similar content being viewed by others

References

  1. D. S. Dabkowski, P. J. Konkol, L. F. Porter, and A. M. Rathbone: U. S. Patent 3,502,462, March 24, 1970.

  2. L. F. Porter: Paper presented at William Hunt Eisenman Conference on Frac-ture Control, American Society for Metals, Philadelphia, Pa., January 27, 1970.

  3. L. F. Porter, S. J. Manganello, D. S. Dabkowski, and J. H. Gross:Metals Eng. Quart., 1966, vol. 6, pp. 17–32.

    Google Scholar 

  4. W. Jolley:J. Iron Steel Inst., 1968, vol. 206, pp. 170–73.

    Google Scholar 

  5. W. C. Leslie, R. J. Sober, S. G. Babcock, and S. J. Green:Trans. ASM, 1969, vol.62, pp. 690–710.

    Google Scholar 

  6. C. Vishnevsky and E. A. Steigerwald:Trans. ASM, 1969, vol. 62, pp. 305–17.

    Google Scholar 

  7. W. C. Leslie and R. J. Sober:Trans. ASM, 1967, vol. 60, pp. 459–84.

    Google Scholar 

  8. G. R. Speich and H. Warlimont:J. Iron Steel Inst., 1968, vol. 206, pp. 385–92.

    Google Scholar 

  9. E. C. Bain:Alloying Elements in Steel, ASM, Cleveland, Ohio, 1939.

    Google Scholar 

  10. K. Kuo:J. Iron Steel Inst., 1956, vol. 184, pp. 258–68.

    Google Scholar 

  11. S. Floreen and G. R. Speich:Trans. ASM, 1964, vol. 57, pp. 714–26.

    Google Scholar 

  12. V. K. Chandhok, J. P. Hirth, and E. J. Dulis:Trans. ASM, 1963, vol. 56, pp. 677–91.

    Google Scholar 

  13. S. Floreen:Trans. ASM, 1964, vol. 57, pp. 38–47.

    Google Scholar 

  14. N. S. Stoloff, R. G. Davies, and R. C. Ku:Trans. TMS-A1ME, 1965, vol. 233, pp. 1500–08.

    Google Scholar 

  15. G. R. Speich and P. R. Swann:J. Iron Steel lnst., 1965, vol. 203, pp. 480–85.

    Google Scholar 

  16. G. R. Speich:Trans. TMS-AIME, 1969, vol. 243, pp. 2553–64.

    Google Scholar 

  17. G. T. Langford and Morris Cohen:Trans. ASM, 1969, vol. 62, pp. 623–38.

    Google Scholar 

  18. J. D. Embury, A. S. Keh and R. M. Fisher:Trans. TMS-AIME, 1966, vol. 236, pp. 1252–60.

    Google Scholar 

  19. E. Orowan:Dislocations in Metals, pp. 69–188, AIME, New York, 1954.

    Google Scholar 

  20. W. C. Leslie, J. T. Michalak, and F. W. Aul:Iron and Its Dilute Solid Solutions, pp. 119–213, Interscience Publishers, New York, 1963.

    Google Scholar 

  21. J. W. Christian:The Theory of Transformation in Metals and Alloys, Pergamon Press, London, 1965.

    Google Scholar 

  22. M. J. Roberts and W. S. Owen:Trans. ASM, 1967, vol. 60, pp. 687–92.

    Google Scholar 

  23. C. W. Marschall, R. F. Hehemann, and A. R. Troiano:Trans. ASM, 1962, vol. 55, pp. 135–48.

    Google Scholar 

  24. G. J. Spaeder: Ph.D. Dissertation, University of Pittsburgh, 1969.

  25. S. Murphy and J. A. Whiteman:Metal Sci., 1970, vol. 4, pp. 58–62.

    Article  Google Scholar 

  26. I. Tamaru, T. Maki, and S. Fujuwara: Supplement Jap. lnst. Metals, 1968, pp. 412-17.

  27. K. W. Andrews and H. Hughes:J. Iron and Steel lnst., 1959, vol. 193. pp. 304–11.

    Google Scholar 

  28. V. K. Chandhok, J. P. Hirth, and E. J. Dulis:Trans. TMS-AIME, 1962, vol. 224, pp. 858–64.

    Google Scholar 

  29. M. R. Banerjee and J. J. Hauser:Transformation and Hardenability in Steels, pp. 133–49, Climax Molybdenum Co., 1967.

  30. J. T. Michalak: Private Communication, U.S. Steel, Monroeville, Pennsylvania, March 1971.

  31. I. C. Polmer and G. C. Smith:Oxide Dispersion Strengthening, pp. 253–90, Gordon and Breach, New York, 1968.

    Google Scholar 

  32. P. P. Puzak and E. A. Lange:Metals Eng. Quart., 1970, vol. 10, pp. 6–16.

    Google Scholar 

  33. G. T. Hahn and A. R. Rosenfeld:Amer. Soc. Testing Mater. Special Tech. Publ. 432, 1968, pp. 6–31.

    Google Scholar 

  34. J. M. Kraft:Appl. Mater. Res., 1964, vol. 3, pp. 88–101.

    Google Scholar 

  35. D. P. Clausing:Int. J. Fract. Mech., 1970, vol. 6, pp. 71–85.

    Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Rights and permissions

Reprints and permissions

About this article

Cite this article

Speich, G.R., Dabkowski, D.S. & Porter, L.F. Strength and toughness of Fe-10ni alloys containing C, Cr, Mo, and Co. Metall Trans 4, 303–315 (1973). https://doi.org/10.1007/BF02649630

Download citation

  • Received:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF02649630

Keywords

Navigation