Journal of Materials Science

, Volume 29, Issue 7, pp 1739–1752 | Cite as

Effect of glass-fibre reinforcement and annealing on microstructure and mechanical behaviour of nylon 6,6

Part II Mechanical behaviour
  • M. L. Shiao
  • S. V. Nair
  • P. D. Garrett
  • R. E. Pollard


The effects of glass-fibre reinforcement and annealing on the deformation and fracture behaviour of nylon 6,6 were investigated. The roles of glass fibres were examined by varying the glass fibre content and the fibre length, and by in situ fracture studies in front of crack tips. The effects of microstructural changes were investigated by imposing various annealing conditions on the specimens. The results indicated that the fracture toughness showed a sharp decrease due to stress concentrations at fibre ends when the fibre volume fraction was small. Above a critical fibre volume fraction, it was found that the fracture toughness can be substantially increased by enhanced localized matrix plasticity at fibre ends. The competing roles of glass fibre ends were consistent with microstructure sensitive fracture mechanics models of failure based on the attainment of a critical stress or strain over a critical microstructural distance in the crack-tip region. Upon annealing above a critical annealing time the unreinforced nylon 6,6 showed a drastic decrease in the strength and ductility, corresponding to a loss of the constant-load deformation region prior to necking. However, the fracture toughness of unreinforced nylon 6,6 was only moderately reduced by annealing. On the other hand, the fracture toughness of the composites showed a significant increase upon annealing. The combined effects of glass fibres and annealing on microstructures and overall property optimization of the composites are also discussed.


Fracture Toughness Glass Fibre Fibre Length Fibre Volume Fraction Localize Matrix 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    M. F. Ashby, Acta Metall. 37 (1989) 1273.CrossRefGoogle Scholar
  2. 2.
    T. Vu-Khanh, Polym. Compos. 8 (1987) 363.CrossRefGoogle Scholar
  3. 3.
    P. K. Mallick, “Fiber-reinforced Composites: Materials, Manufacturing and Design” (Marcel Dekker, New York, 1988) p. 1.Google Scholar
  4. 4.
    D. W. Clegg and A. A. Collyer (eds), “Mechanical Properties of Reinforced Thermoplastics” (Applied Science, New York, 1986).Google Scholar
  5. 5.
    W. V. Totow and B. J. Lanham, “Reinforced Thermoplastics” (Applied Science, London, 1975) p. 1.Google Scholar
  6. 6.
    M. J. Folkes, “Short Fiber Reinforced Thermoplastics” (Research Studies Press, Chichester, 1982) p. 31.Google Scholar
  7. 7.
    P. T. Curtis, M. G. Bader and J. E. Bailey, J. Mater. Sci. 13 (1978) 377.CrossRefGoogle Scholar
  8. 8.
    N. Sato, T. Kurauchi, S. Sato and O. Kamigaito, ibid. 26 (1991) 3891.CrossRefGoogle Scholar
  9. 9.
    K. Takahashi and N. S. Choi, ibid. 26 (1991) 4648.CrossRefGoogle Scholar
  10. 10.
    S. V. Nair, M. L. Shiao and P. D. Garrett, ibid. 27 (1992) 1085.CrossRefGoogle Scholar
  11. 11.
    B. Lauke, B. Schultrich and W. Pompe, Polym. Plast. Technol. Eng. 29 (1990) 607.CrossRefGoogle Scholar
  12. 12.
    J. M. Schultz, Polym. Eng. Sci. 24 (1984) 770.CrossRefGoogle Scholar
  13. 13.
    A. J. Kinloch and R. J. Young, “Fracture Behavior of Polymers” (Applied Science, London, 1983) Ch. 9.Google Scholar
  14. 14.
    A. Peterlin, J. Appl. Phys. 35 (1964) 75.CrossRefGoogle Scholar
  15. 15.
    E. W. Fisher, Pure Appl. Chem. 31 (1972) 113.CrossRefGoogle Scholar
  16. 16.
    H. W. Starkweather Jr, G. E. Moore, J. E. Hansen, T. M. Roder and R. E. Brooks, J. Polym. Sci. XXI (1956) 189.CrossRefGoogle Scholar
  17. 17.
    G. C. Alfonso, E. Pedemonte and C. Ponzetti, Polymer 20 (1979) 104.CrossRefGoogle Scholar
  18. 18.
    D. P. Russell and P. W. R. Beaumont, J. Mater. Sci. 15 (1980) 216.CrossRefGoogle Scholar
  19. 19.
    J. P. Bell and J. H. Dumbleton, J. Polym. Sci. A-2 7 (1969) 1033.CrossRefGoogle Scholar
  20. 20.
    R. Elenga, R. Seguela and F. Rietsch, Polymer 32 (1991) 1975.CrossRefGoogle Scholar
  21. 21.
    R. S. Schotland, Polym. Eng. Sci. 6 (1966) 244.CrossRefGoogle Scholar
  22. 22.
    B. Wunderlich, “Macromolecular Physics”, Vol. 3 (Academic Press, New York, 1980) Ch. 9.Google Scholar
  23. 23.
    M. J. McCready and J. M. Schultz, J. Polym. Sci. Polym. Phys. 17 (1979) 725.CrossRefGoogle Scholar
  24. 24.
    S. Nagou and S. Oba, J. Macromol. Sci. Phys. B18 (1980) 281.CrossRefGoogle Scholar
  25. 25.
    G. P. Desio and L. Rebenfeld, J. Appl. Polym. Sci. 39 (1990) 825.CrossRefGoogle Scholar
  26. 26.
    T. Bessell and J. B. Shortfall, J. Mater. Sci. 10 (1975) 2035.CrossRefGoogle Scholar
  27. 27.
    M. L. Shiao, S. V. Nair, P. D. Garrett and R. E. Pollard, ibid. (1994).CrossRefGoogle Scholar
  28. 28.
    “Protocal on Plain-Strain Fracture Toughness and Strain Energy Release Rate of Plastic Materials”, ASTM Subcommittee D20.10.21 (American Society for Testing and Materials, Philadelphia, PA, 1989).Google Scholar
  29. 29.
    P. Chang and J. A. Donovan, J. Mater. Sci. 24 (1989) 816.CrossRefGoogle Scholar
  30. 30.
    B. D. Aggarwala and E. Saibel, Phys. Chem. Glasses 2 (1961) 137.Google Scholar
  31. 31.
    T. J. Bessell, D. Hull and J. B. Shortfall, J. Mater. Sci. 10 (1975) 1127.CrossRefGoogle Scholar
  32. 32.
    J. C. Haplin and J. L. Kardos, Polym. Eng. Sci. 16 (1976) 344.CrossRefGoogle Scholar
  33. 33.
    M. I. Kohan (ed.), “Nylon Plastics” (Wiley, New York, 1973) p. 333.Google Scholar
  34. 34.
    P. Chang, PhD thesis, University of Massachusetts, Amherst (1992).Google Scholar
  35. 35.
    Y. Liu and J. A. Donovan, private communication (1992).Google Scholar
  36. 36.
    E. Dobrovolny-Marand, PhD thesis, University of Massachusetts, Amherst (1987).Google Scholar
  37. 37.
    B. Budiansky, J. W. Hutchinson and J. C. Lambropoulos, Int. J. Solids Struct. 19 (1983) 337.CrossRefGoogle Scholar
  38. 38.
    R. K. Pandey and S. Banerjee, Int. Fract. Mech. 10 (1978) 817.CrossRefGoogle Scholar
  39. 39.
    R. O. Ritchie, W. L. Server and R. A. Wullaert, Metall. Trans. 10A (1979) 1557.CrossRefGoogle Scholar
  40. 40.
    J. R. Rice and M. A. Johnson, “Inelastic Behavior of Solids”, edited by M. F. Kanninen, W. F. Adler, A. R. Rosenfield and R. I. Jaffee, (McGraw Hill, New York, 1970) p. 641.Google Scholar
  41. 41.
    S. V. Nair and M. L. Shiao, to be published.Google Scholar
  42. 42.
    F. J. Padden and H. D. Keith, J. Appl. Phys. 30 (1959) 1479.CrossRefGoogle Scholar
  43. 43.
    N. Sato, T. Kurauchi, S. Sato and O. Kamigaito, J. Compos. Mater. 22 (1988) 850.CrossRefGoogle Scholar
  44. 44.
    J. C. Watkins, P. C., Gaa and R. G. Swisher, in “Proceedings of the ANTEC '88”, Atlanta, April 1988 (Society of Plastic Engineers, Brookfield, CT, 1988) p. 528.Google Scholar

Copyright information

© Chapman & Hall 1994

Authors and Affiliations

  • M. L. Shiao
    • 1
  • S. V. Nair
    • 1
  • P. D. Garrett
    • 2
  • R. E. Pollard
    • 2
  1. 1.Department of Mechanical EngineeringUniversity of MassachusettsAmherstUSA
  2. 2.Monsanto Chemical Co.SpringfieldUSA

Personalised recommendations