Journal of Materials Science

, Volume 40, Issue 7, pp 1615–1623

Tensile strength and fracture surface characterisation of sized and unsized glass fibers



The tensile strength of commercial glass fibers is examined by single fiber tensile tests. The fibers are analysed as received from the manufacturer (sized) and after a heat treatment at 500C (unsized). Weibull plots of the two series are used for comparison of the strengths of the sized and unsized fibers. It is shown that large sample sizes (over 60 tests) are required to lead to a reliable two-parameter Weibull distribution. The experimental tests clearly indicated that the unsized fibers were weaker in the low strength range, but had similar strength in the high strength range. An investigation of the fracture surfaces in the SEM showed distinct differences in the fracture patterns for high and low strength fibers. Fracture mechanics were applied to estimate the original flaw size and relate the observed fracture mirror surface to the fiber strength. Based on the observation of surface flaws, a “healing” mechanism by the sizing is considered likely for this type of fiber and sizing, thereby effectively increasing the strength of the fiber in the presence of larger surface flaws.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    W. WEIBULL, The Royal Swedish Institute for Engineering Research, Stockholm, 1939, No. 151.Google Scholar
  2. 2.
    P. ZINCK, M. F. PAYS, R. REZAKHANLOU and J. F. GERARD, J. Mat. Sci. 34 (1999) 2121.Google Scholar
  3. 3.
    T. H. CHENG, F. R. JONES and D. WANG, Comp. Sci. Techn. 48 (1993) 89.Google Scholar
  4. 4.
    F. M. ZHAO and N. TAKEDA, Comp. Part A. 31 (2000) 1203.Google Scholar
  5. 5.
    P. ZINCK, E. MAEDER and J. F. GERARD, J. Mat. Sci. 36 (2001) 5245.Google Scholar
  6. 6.
    S. FEIH, J. WEI, P. K. KINGSHOTT and B. F. SOERENSEN, Comp. Part A 36 (2005) 245.Google Scholar
  7. 7.
    P. K. GUPTA, in “Fibre Reinforcements for Composite Materials,” edited by A. R. Busnell (Elsevier Science Publishers A.V., 1988) p. 19.Google Scholar
  8. 8.
    S. M. WIEDERHORN, J. Am. Ceram. Soc. 50 (1967) 407.Google Scholar
  9. 9.
    E. B. SHAND, ibid. 42 (1959) 474.Google Scholar
  10. 10.
    J. J. MECHOLSKY, R. W. RICE and S. W. FREIMAN, ibid. 57 (1974) 440.Google Scholar
  11. 11.
    R. J. CASTILONE, G. S. GLAESEMAN and T. A. HANSON, in Proceedings of SPIE 4639 on Optical Fiber and Fiber Component Mechanical Reliability and Testing II, 2002, p. 11.Google Scholar
  12. 12.
    M. D. THOULESS, O. SBAIZERO, L. S. SIGL and A. G. EVANS, J. Am. Ceram. Soc. 72 (1989) 525.Google Scholar
  13. 13.
    E. CENDRE, S. FEIH and M. STAMPIONI, in “PSI Scientific Report,” (2003) Vol. VII, p. 56.Google Scholar
  14. 14.
    H. W. COLEMAN and W. G. STEELE, in “Experimentation and Uncertainty Analysis for Engineers” (John Wiley and Sons, Inc., 1999) p. 54.Google Scholar
  15. 15.
    A. KHALILI and K. KROMP, J. Mat. Sci. 26 (1991) 6741.Google Scholar
  16. 16.
    D. WANG and F. R. JONES, Surf. Interf. Anal. 20 (1993) 457.Google Scholar
  17. 17.
    H. ISHIDA, S. NAVIROJ, S. K. TRIPATHY, J. J. FITZGERALD and J. L KOENIG, J. Pol. Sci. Part B. 20 (1982) 701.Google Scholar
  18. 18.
    S. M. WIEDERHORN, J. Am. Ceram. Soc. 52 (1969) 99.Google Scholar
  19. 19.
    D. A. KROHN and D. P. H. HASSELMAN, ibid. 54 (1971) 411.Google Scholar
  20. 20.
    W. T. KOITER, J. Appl. Mech. 32 (1965) 237.Google Scholar
  21. 21.
    A. LEVAN and J. ROYER, Int. J. Fract. 61 (1993) 71.Google Scholar

Copyright information

© Springer Science + Business Media, Inc. 2005

Authors and Affiliations

  1. 1.Materials Research DepartmentRisø National LaboratoryRoskildeDenmark

Personalised recommendations