Metallurgical Transactions A

, Volume 23, Supplement 1, pp 3281–3291 | Cite as

Void nucleation in constrained silver interlayers

  • R. J. Klassen
  • G. C. Weatherly
  • B. Ramaswami
Mechanical Behavior


The process of void nucleation during fracture in thin brazed Ag interlayers has been investigated. Tensile tests were performed on interlayers of five thicknesses. The tensile strength increased rapidly with the ratio of interlayer diameter to thickness(D/T) for the thick interlayers(D/T < approximately 40) while the rate decreased significantly in the thin interlayers. All specimens fractured in the Ag interlayer along a plane near, and parallel to, the steel interface. The fracture surfaces showed silicon oxide inclusions at the bottom of many of the dimples. A series of finite element models were constructed to determine the general stress state in the interlayers and to determine the development of local stresses around inclusions in the interlayer. The finite ele- ment calculations indicated that the distribution of triaxial tension radially across the interlayer varied withD/T. Triaxial stresses, at failure, up to 10 times the uniaxial yield stress of the Ag were predicted from the model. The local stresses around a rigid inclusion in the interlayer developed more quickly, with applied stress, in the thicker interlayers as a result of the increased plastic deformation. The development of local stresses also increased with the proximity of the inclusion to the steel interface. By assuming a critical stress criterion for void nucleation at an inclusion interface, the finite element model was able to predict the experimentally observed nonlinear relationship between the interlayer failure stress andD/T.


Metallurgical Transaction Triaxial Stress Void Nucleation Rigid Inclusion Interlayer Thickness 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    S. Floreen and H.W. Hayden:Scripta Metall., 1970, vol. 4, pp. 87–94.CrossRefGoogle Scholar
  2. 2.
    T.B. Cox and J.R. Low, Jr.:Metall. Trans., 1974, vol. 5, pp. 1457–70.CrossRefGoogle Scholar
  3. 3.
    M.N. Bassim, R.J. Klassen, M.R. Bayoumi, and H.G.F. Wilsdorf:Mater. Sci. Eng., 1987, vol. 92, pp. 107–11.CrossRefGoogle Scholar
  4. 4.
    D. Kwon and R.J. Asaro:Metall. Trans. A, 1990, vol. 21A, pp. 117–34.ADSGoogle Scholar
  5. 5.
    M.F. Ashby, F.J. Blunt, and M. Bannister:Acta Metall., 1989, vol. 37, pp. 1847–57.CrossRefGoogle Scholar
  6. 6.
    F.A. McClintock:J. Appl. Mech., 1968, vol. 35, pp. 363–71.Google Scholar
  7. 7.
    J.R. Rice and D.M. Tracey:J. Mech. Phys. Solids, 1969, vol. 17, pp. 201–17.CrossRefADSGoogle Scholar
  8. 8.
    D.M. Tracey:J. Mech. Phys. Solids, 1971, vol. 3, pp. 301–15.Google Scholar
  9. 9.
    R.J. Boucier, D.A. Koss, R.E. Smelser, and O. Richmond:Acta Metall., 1986, vol. 34, pp. 2443–53.CrossRefGoogle Scholar
  10. 10.
    N. Aravas and R.M. McMeeking:J. Mech. Phys. Solids, 1985, vol. 33, pp. 25–49.CrossRefADSGoogle Scholar
  11. 11.
    N. Aravas and R.M. McMeeking:Int. J. Fract., 1985, vol. 29, pp. 21–38.CrossRefGoogle Scholar
  12. 12.
    V. Tvergaard:Acta Metall., 1991, vol. 39, pp. 419–26.CrossRefGoogle Scholar
  13. 13.
    A.S. Argon, J. Im, and R. Safoglu:Metall. Trans. A, 1975, vol. 6A, pp. 825–37.ADSGoogle Scholar
  14. 14.
    A.S. Argon and J. Im:Metall. Trans. A, 1975, vol. 6A, pp. 839–51.ADSGoogle Scholar
  15. 15.
    S.H. Goods and L.M. Brown:Acta Metall., 1979, vol. 27, pp. 1–15.CrossRefGoogle Scholar
  16. 16.
    J.R. Fisher and J. Gurland:Met. Sci., 1981, vol. 15, pp. 185–92.CrossRefGoogle Scholar
  17. 17.
    J.R. Fisher and J. Gurland:Met. Sci., 1981, vol. 15, pp. 193–202.Google Scholar
  18. 18.
    I.E. Orowan:Trans. Eng. Shipbuilders Scotland, 1945, vol. 89, pp. 165–215.Google Scholar
  19. 19.
    I.E. Orowan, J.F. Nye, and W.J. Cairns:M.O.S. Armament Res. Dept. Rep., 1945, vol. 16, p. 35.Google Scholar
  20. 20.
    N. Bredzs:Weld. J., 1954, vol. 33, pp. 545s-63s.Google Scholar
  21. 21.
    N. Bredzs and H. Schwartzbart:Weld. J., 1956, vol. 35, pp. 610s-15s.Google Scholar
  22. 22.
    W.G. Moffat and J. Wulff:Trans. AIME, 1957, vol. 209, pp. 442–45.Google Scholar
  23. 23.
    W.G. Moffat and J. Wulff:Weld. J., 1963, vol. 42, pp. 115s-25s.Google Scholar
  24. 24.
    J.R. Griffiths and J.A. Charles:Met. Sci. J., 1968, vol. 2, pp. 89–92.CrossRefGoogle Scholar
  25. 25.
    H.J. Saxton, A.J. West, and C.R. Barrett:Metall. Trans., 1971, vol. 2, pp. 999–1007.CrossRefGoogle Scholar
  26. 26.
    A.J. West, H.J. Saxton, A.S. Tetelman, and C.R. Barrett:Metall. Trans., 1971, vol. 2, pp. 1009–17.CrossRefGoogle Scholar
  27. 27.
    E.A. Almond, D.K. Brown, G.J. Davies, and A.M. Cottenden:Int. J. Mech. Sci., 1983, vol. 25, pp. 175–89.CrossRefGoogle Scholar
  28. 28.
    B.J. Dalgleish, M.C. Lu, and A.G. Evans:Acta Metall., 1988, vol. 36, pp. 2029–35.CrossRefGoogle Scholar
  29. 29.
    B.J. Dalgleish, K.P. Trumble, and A.G. Evans:Acta Metall., 1989, vol. 37, pp. 1923–31.CrossRefGoogle Scholar
  30. 30.
    E.E. Underwood:Quantitative Stereology, Addison-Wesley, Reading, MA, 1970.Google Scholar
  31. 31.
    R.J. Klassen: Ph.D. Thesis, University of Toronto, Toronto, ON, 1990.Google Scholar
  32. 32.
    R.J. Klassen, G.C. Weatherly, and B. Ramaswami: University of Toronto, Toronto, ON, unpublished research, 1990.Google Scholar

Copyright information

© The Minerals, Metals & Materials Society - ASM Materials - The Materials Information Society 1992

Authors and Affiliations

  • R. J. Klassen
    • 1
  • G. C. Weatherly
    • 2
  • B. Ramaswami
    • 3
  1. 1.Atomic Energy of Canada Ltd.Chalk RiverCanada
  2. 2.Department of Materials ScienceMcMaster UniversityHamiltonCanada
  3. 3.Department of Metallurgy and Materials ScienceUniversity of TorontoTorontoCanada

Personalised recommendations