Skip to main content
SpringerLink
Log in

Fatigue Crack initiation and microcrack growth in 2024-T4 and 2124-T4 aluminum alloys

  • Published:
Metallurgical Transactions A Aims and scope Submit manuscript

Abstract

A metallograph was mounted directly on a closed-loop electrohydraulic testing unit and initiation of fatigue cracks was directly observed on polished notches at magnifications up to 800 times in aluminum alloys 2024 and 2124 in the T-4 condition. The latter is a high purity version of 2024 and contains considerably fewer constituent particles. At high stresses on the notch surface the fatigue cracks initiated on coarse slip lines in both alloys. At low stresses almost all of the cracks in 2024 initiated in the matrix adjacent to constituent particles. In 2124 at low stresses 50 pct of the cracks initiated near constituent particles and 50 pct in the matrix not near constituent particles. The probability that a constituent particle in 2024 initiates a fatigue crack falls off very rapidly as the particle size decreases below 6 μm. Growth of microcracks is impeded by grain boundaries.

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

Access this article

Log in via an institution

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. M. S. Hunter and W. G. Fricke:Proc. ASTM, 1954, vol. 54, p. 717.

    CAS  Google Scholar 

  2. J. C. Grosskreutz and G. G. Shaw:Proc. of 2nd Int. Conf. on Fracture, P. L. Pratt, ed., pp. 620–29, Chapman and Hall, London 1969.

    Google Scholar 

  3. R. E. Peterson:Metal Fatigue, G. Sines and J. L. Waisman, eds., Chap. 13, McGraw-Hill, NY, 1959.

    Google Scholar 

  4. Y. Kung: Ph.D. Dissertation, Northwestern University, Evanston, Ill., 1978.

  5. P. J. E. Forsyth:J. Inst. Metals, 1951–52, vol. 80, p. 181:ibid., 1953–54, vol. 82, p. 449; Nature, Lond., 1953, vol. 171, p. 172; Int. Conf. on Fatigue, Institution of Mechanical Engineers, 1956, p. 135; Phil. Mag., 1957, vol. 2, p. 437; Proc. Roy. Soc, 1957, vol. A242, p. 198; P. J. E. Forsyth and A. Stubbington: Nature, Lond., 1955, vol. 175, p. 767; J. Inst. Metals, 1954-55, vol. 83, p. 173; ibid., 1954-55, vol. 83, p. 395; ibid., 1956–57, vol. 85, p. 339; A. Stubbington and P. J. E. Forsyth: J. Inst. Metals, 1957–58, vol. 86, p. 90.

    CAS  Google Scholar 

  6. Laird and D. J. Duquette: NACE-2, pp. 88–117, University of Connecticut, Storrs, Conn., 1972.

  7. G. R. Irwin:Trans. ASME, Scr. E. J. Appl. Mech., 1962, vol. 29, pp. 651–654.

    Google Scholar 

  8. W. F. Brown, and J. E. Strawley: ASTM STP 410, 1967.

  9. W. L. Morris:Met. Trans. A, 1977, vol. 8A,p. 1079; ibid.,p. 1087; ibid., p. 589; W. L. Morris and O. Buck, ibid., p. 597; W. L. Morris, O. Buck and H.L.Marcus: Met. Trans. A, 1976,vol. 7A,p. 1161.

    CAS  Google Scholar 

  10. T. Yokobori, M. Uozumi and M. Ichikawa: Reports of the Research Institute for Strength and Fracture of Materials, 1971, vol. 7, No. l,p.25;A. Kamei and T. Yokobori: ibid., 1974, vol. 10, No. 2, p. 45.

Download references

Author information

Authors and Affiliations

  1. Department of Metallurgical Engineering, Georgia Institute of Technology, 30332, Atlanta, GA

    C. Y. Kung (Postdoctoral Research Associate)

  2. Northwestern University, 60201, Evanston, IL

    M. E. Fine (W.P. Murphy Professor of Materials Science and Engineering)

Authors
  1. C. Y. Kung
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. M. E. Fine
    View author publications

    You can also search for this author in PubMed Google Scholar

Additional information

This research was done at Northwestern University.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Kung, C.Y., Fine, M.E. Fatigue Crack initiation and microcrack growth in 2024-T4 and 2124-T4 aluminum alloys. Metall Trans A 10, 603–610 (1979). https://doi.org/10.1007/BF02658324

Download citation

  • Received:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF02658324

Keywords

Search

Navigation