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Journal of Sol-Gel Science and Technology

, Volume 2, Issue 1–3, pp 211–214 | Cite as

Weibull analysis of the mechanical strength of silica gels

Code: C3
  • L. Duffours
  • F. Pernot
  • T. Woignier
  • A. Alaoui
  • J. Phalippou
Article

Abstract

Since gels are typically brittle materials, reliable analyses are essential to determine the strength distribution. The mechanical strength of silica gels has been measured by the three point bending technique. Based on the Weibull function, the statistical analysis allows determination of the Weibull modulus (m), which characterizes the strength distribution and the flaw size effect.

Two kinds of gels, alcogels and aerogels, have been investigated with respect to their different mechanical behaviour owing to the transformations occurring during the supercritical drying (SD). The toughness of the two materials has been also measured by the SENB technique. It appears that the strength increases by a factor greater than two during SD, the KIC increases slightly. However, m is not greatly affected which would suggest that SD does not induce significant flaws or defects change in the network.

Keywords

Weibull analysis mechanical properties toughness 

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References

  1. 1.
    Scherer, G.W., Pardenek, S.A., and Swiatek, R.M., J. Non-Cryst. Solids, 107, 14, (1988).Google Scholar
  2. 2.
    Pardenek, S. A., Fleming, J. W., Klein, L. C., Mater. Res. Soc. Symp. Proc. 88, 73 (1987).Google Scholar
  3. 3.
    Woignier, T. and Phalippou, J., J. Non-Cryst. Solids 100, 325 (1988).Google Scholar
  4. 4.
    Scherer, G.W., J. Non-Cryst. Solids 109, 183 (1989).Google Scholar
  5. 5.
    Woignier, T., Phalippou, J., Hdach, H., and Scherer, G.W., in Better Ceramics through Chemistry IV: Mater. Res. Soc. Proc. 180, 1087 (1990).Google Scholar
  6. 6.
    Griffith, A.A., Phil. Trans. Roy. Soc. Lon., 221A, 163 (1920).Google Scholar
  7. 7.
    Inglis, G.E., Inst. Nanal. Archetects Trans., 55, (1913).Google Scholar
  8. 8.
    Irwin, G.E., Trans. ASM, 40A, 47 (1948).Google Scholar
  9. 9.
    Zarzycki, J., J. Non-Cryst. Solids, 100, 255 (1988).Google Scholar
  10. 10.
    Rogier, R., Woignier, T., and Phalippou, J., Rev. Phys. Appl., 24 (C4), 197 (1989).Google Scholar
  11. 11.
    Woignier, T., Phalippou, J., Hdach, H., Larnac, G., Pernot, F., and Scherer, G.W., J. Non-Cryst. Solids, 147–148, 672 (1992).Google Scholar
  12. 12.
    Scherer, G.W., J. Non-Cryst. Solids 144, 210 (1992).Google Scholar
  13. 13.
    Scherer, G. W., J. Non-Cryst. Solids 147–148, 383 (1992)Google Scholar
  14. 14.
    Evans, A.G. and Tappin, G., Proc. Brit. Ceram. Soc., 23, 275 (1972).Google Scholar
  15. 15.
    Chermant, J.L. and Osterstock, F.J. Mater. Sci., 14, 1939 (1976).Google Scholar
  16. 16.
    Scherer, G.W., J. Non-Cryst. Solids, 145, 33 (1992).Google Scholar
  17. 17.
    Weibull, W., J. Appl. Mech., 18(3), 293 (1951).Google Scholar
  18. 18.
    Sullivan, J.D. and Lauzon, P.H., J. Mater. Sci. Letters, 5(11), 1245 (1986).Google Scholar
  19. 19.
    Batdorf, S.B., in Fracture Mechanics of Ceramics, Vol. 3, edited by Bradt, R.C., Hasselman, D.P.H., F, Lange (Plenum Press, New York, 1978) p. 1.Google Scholar
  20. 20.
    Katayama, Y. and Hattori, Y., J. Amer. Cer. Soc., 52 (10), C-164 (1982).Google Scholar
  21. 21.
    Scott, W.D. and Gaddipati, A., in Fracture Mechanics of Ceramics, Vol. 3, edited by Bradt, R.C., Hasselman, D.P.H., F, Lange (Plenum Press, New York, 1978) p. 125.Google Scholar
  22. 22.
    Barrera Solano, M.C., De la Rosa Fox, N., and Esquivias, L., J. Non-Cryst. Solids, 147–148, 194 (1992).Google Scholar
  23. 23.
    Woignier, T., Phalippou, J., Quinson, J.F., Pauthe, M., and Lavessiere, F., J. Non-Cryst. Solids, 145, 25 (1992).Google Scholar
  24. 24.
    Gibson, L.J. and Ashby, M.F., Cellular Solids (Academic Press, New York 1988).Google Scholar
  25. 25.
    Maiti, S.K. and Gibson, L.J., Scr. Metall., 18, 213 (1984).Google Scholar
  26. 26.
    Brenzy, R. and Green, D.J., J. Amer. Cer. Soc., 74(5), 1061 (1991).Google Scholar
  27. 27.
    Rice, R.W., “Treatise on materials science and technology,” Vol. II, MacCrone R.K., ed., Acad. Press, (1977), Paris.Google Scholar

Copyright information

© Kluwer Academic Publishers 1994

Authors and Affiliations

  • L. Duffours
    • 1
  • F. Pernot
    • 1
  • T. Woignier
    • 1
  • A. Alaoui
    • 1
  • J. Phalippou
    • 1
  1. 1.L.S.M.V., Université de Montpellier IIMontpellier Cedex 5

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