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Fatigue crack propagation in aluminum-lithium alloy 2090: Part II. small crack behavior

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Abstract

A study has been made of the mechanics and mechanisms of fatigue crack propagation in a commercial plate of aluminum-lithium alloy 2090-T8E41. In Part II, the crack growth behavior of naturallyoccurring, microstructurally-small (2 to 1000µm) surface cracks is examined as a function of plate orientation, and results compared with those determined in Part I on conventional long (≳5 mm) crack samples. It is found that the near-threshold growth rates of small cracks are between 1 to 3 orders of magnitude faster than those for long cracks, subjected to the same nominal stress intensity ranges (at a load ratio of 0.1). Moreover, the small cracks show no evidence of an intrinsic threshold and propagate at ΔK levels as low as 0.7 MPa{ie563-01}, far below the long crack threshold ΔKTH. Their behavior is also relatively independent of orientation. Such accelerated small crack behavior is attributed primarily to restrictions in the development of crack tip shielding (principally from roughness-induced crack closure) with cracks of limited wake. This notion is supported by the close correspondence of small crack results with long crack growth rates plotted in terms of ΔKeff (i.e., after allowing for closure above the effective long crack threshold). Additional factors, including the different statistical sampling effect of large and small cracks with microstructural features, are briefly discussed.

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References

  1. Anon: “Airplane Damage Tolerance Requirements”, Military Specification MIL-A-83444, United States Air Force, July 1974.

  2. S. J. Hudak:J. Eng. Math. Tech., Trans. ASME, Series H, 1981, vol. 103, pp. 26–35.

    Article  CAS  Google Scholar 

  3. J. Schijve: inFatigue Thresholds, J. Bäcklund, A. F. Blom, and C. J.Beevers, eds., EMAS Ltd., Warley, U.K., 1982, vol. 2, pp. 881–908.

    Google Scholar 

  4. K. J. Miller:Fat. Eng. Mat. Struct., 1982, vol. 5, pp. 223–32.

    Article  Google Scholar 

  5. S. Suresh and R. O. Ritchie:Int. Metals Reviews, 1984, vol. 29, pp. 445–76.

    Google Scholar 

  6. R. P. Gangloff and R. O. Ritchie: inFundamentals of Deformation and Fracture, B. A. Bilby, K. J. Miller, and J. R. Willis, eds., Cambridge University Press, Cambridge, U.K., 1985, pp. 529–58.

    Google Scholar 

  7. J. Lankford:Fat. Fract. Eng. Mat. Struct., 1983, vol. 8, pp. 161–75.

    Article  Google Scholar 

  8. R. O. Ritchie and J. Lankford:Mater. Sci. Eng., 1986, vol. 84, pp. 11–16.

    Article  Google Scholar 

  9. Small Fatigue Cracks, R. O. Ritchie and J. Lankford, eds., TMS- AIME, Warrendale, PA, 1986.

    Google Scholar 

  10. J. F. McCarver and R. O. Ritchie:Mater. Sci. Eng., 1982, vol. 55, pp. 63–67.

    Article  Google Scholar 

  11. K. Tanaka and Y. Nakai:Fat. Eng. Mat: Struct., 1983, vol. 6, pp. 315–27.

    Article  Google Scholar 

  12. J. Lankford and D. L. Davidson: in Ref. 9, pp. 51–71.

  13. L. Wagner, J. K. Gregory, A. Gysler, and G. Lütjering: in Ref. 9, pp. 117–28.

  14. A. Pineau: in Ref. 9, pp. 191–211.

  15. M. R. James and W. L. Morris: in Ref. 9, pp. 145–56.

  16. K. Tanaka: in Ref. 9, pp. 343–61.

  17. W.L. Morris:Metall. Trans. A, 1980, vol. 11A, pp. 1117–23.

    CAS  Google Scholar 

  18. R. O. Ritchie and W. Yu: in Ref. 9, pp. 167–89.

  19. F. Heubaum and M. E. Fine:Scripta Metall., 1984, vol. 18, pp. 1235–40.

    Article  Google Scholar 

  20. K. Minakawa, H. Nakamura, and A. J. McEvily:Scripta Metall., 1984, vol. 18, pp. 1371–74.

    Article  Google Scholar 

  21. E. Zaiken and R. O. Ritchie:Metall. Trans. A, 1985, vol. 16A, pp. 1467–77.

    CAS  Google Scholar 

  22. K. T. Venkateswara Rao, W. Yu, and R. O. Ritchie:Scripta Metall., 1986, vol. 20, pp. 1459–65.

    Article  CAS  Google Scholar 

  23. R. P. Gangloff and R. P. Wei: in Ref. 9, pp. 239–64.

  24. K. T. Venkateswara Rao, W. Yu, and R. O. Ritchie:Metall. Trans. A, 1988, vol. 19A, pp. 549–61.

    CAS  Google Scholar 

  25. B. S. Majumdar and S. J. Burns:Acta Metall., 1981, vol. 29, pp. 579–88.

    Article  CAS  Google Scholar 

  26. J. Petit, S. Suresh, A. K. Vasudévan, and R. C. Malcolm: inAluminium-Lithium Alloys III, C. Baker, P. J. Gregson, S. J. Harris, and C. J. Peel, eds., Institute of Metals, London, U.K., 1986, pp. 257–62.

    Google Scholar 

  27. K. V. Jata and E. A. Starke: inAluminium-Lithium Alloys III, C. Baker, P. J. Gregson, S. J. Harris, and C. J. Peel, eds., Institute of Metals, London, U.K., 1986, pp. 247–56.

    Google Scholar 

  28. M. Peters, K. Welpmann, W. Zink, and T. H. Sanders: inAluminium- Lithium Alloys III, C. Baker, P.J. Gregson, S.J. Harris, and C.J. Peel, eds., Institute of Metals, London, U.K., 1986, pp. 239–46.

    Google Scholar 

  29. W. Yu and R.O. Ritchie:J. Eng. Math. Tech., Trans. ASME, Series H, 1987, vol. 109, pp. 81–85.

    Article  CAS  Google Scholar 

  30. J. C. Nwman, Jr. and I. S. Raju:Eng. Fract. Mech., 1981, vol. 15, pp. 185–92.

    Article  Google Scholar 

  31. M.R. James:Scripta Metall., 1987, vol. 21, pp. 783–88.

    Article  CAS  Google Scholar 

  32. S. Suresh and R.O. Ritchie: inFatigue Crack Growth Threshold Concepts, D.L. Davidson and S. Suresh, eds., TMS-AIME, Warrendale, PA, pp. 227–61.

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Authors and Affiliations

  1. Department of Materials Science and Mineral Engineering, University of California, 94720, Berkeley, CA

    K. T. Venkateswara Rao (Graduate Student), W. Yu (Research Associate) & R. O. Ritchie (Professor and Director)

  2. Center for Advanced Materials, Lawrence Berkeley Laboratory, 94720, Berkeley, CA

    R. O. Ritchie (Professor and Director)

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  1. K. T. Venkateswara Rao
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  2. W. Yu
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  3. R. O. Ritchie
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Rao, K.T.V., Yu, W. & Ritchie, R.O. Fatigue crack propagation in aluminum-lithium alloy 2090: Part II. small crack behavior. Metall Trans A 19, 563–569 (1988). https://doi.org/10.1007/BF02649270

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