Skip to main content

Summary

The uniaxial tensile creep behaviour of several thermoplastics reinforced with short glass fibres has been studied over a wide range of temperatures using specimens machined from a variety of injection moulded bars, discs and plaques. The samples cover a range of fibre volume fractions from 0,10 to 0.22 and mean fibre aspect ratios from 18.5 to 43.0. A detailed quantitative assessment of fibre orientation distribution (FOD) and fibre length distribution has been carried out for each type of moulding used with each material. This structural information, together with fibre volume fraction, fibre modulus and matrix creep data, has been used in the prediction of composite tensile modulus both parallel and transverse to the major flow direction for each type of moulding. For the theoretical predictions, the FOD was treated using the ‘laminate analogy’ approach developed by Halpin et al; the properties of a ply containing uniaxially aligned short fibres being calculated using several different theoretical approaches. At low strains, one of these approaches led to remarkably good agreement between theoretical and experimental composite moduli, over most of the very wide range of materials and temperatures studied. An empirical extension of this approach is also shown to give reasonably accurate predictions of composite creep behaviour at finite strains, where both the matrix and the composite exhibit non-linear viscoelastic behaviour.

This is a preview of subscription content, log in via an institution to check access.

Access this chapter

Chapter
USD 29.95
Price excludes VAT (USA)
  • Available as PDF
  • Read on any device
  • Instant download
  • Own it forever
eBook
USD 39.99
Price excludes VAT (USA)
  • Available as PDF
  • Read on any device
  • Instant download
  • Own it forever
Softcover Book
USD 54.99
Price excludes VAT (USA)
  • Compact, lightweight edition
  • Dispatched in 3 to 5 business days
  • Free shipping worldwide - see info

Tax calculation will be finalised at checkout

Purchases are for personal use only

Institutional subscriptions

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. L.N. Philips, Fabrication of reinforced thermoplastics by means of the film stacking technique, in: “Fabrication Techniques for Advanced Reinforced Plastics”, Proceedings of Symposium at Salford University, UK, April, 1980, IPC Science and Technology Press, Guildford, UK(1980).

    Google Scholar 

  2. M.W. Darlington, B.K. Gladwell and G.R. Smith, Structure and properties in injection moulded discs of glass fibre reinforced polypropylene, Polymer, 18; 1269 (1977).

    Article  CAS  Google Scholar 

  3. M.W. Darlington, P.L. McGinley and G.R. Smith, Structure and anisotropy of stiffness in glass fibre reinforced thermoplastics, J. Mater. Sci., 11: 877 (1976).

    Article  Google Scholar 

  4. D. McNally, Short fibre orientation and its effects on the properties of thermoplastic composite materials, Polym. Plast. Technol. Eng., 8: 101 (1977).

    Article  CAS  Google Scholar 

  5. P.F. Bright and M.W. Darlington, Factors influencing fibre orientation and mechanical properties in fibre reinforced thermoplastics injection mouldings, Plastics and Rubber Processing and Applications, 1: 139 (1981).

    CAS  Google Scholar 

  6. R.C. Stephenson, Design information for thermoplastic composites; coupled glass-fibre-reinforced polypropylene, Plastics and Rubber: Mats, and Applications, 4: 45 (1979).

    CAS  Google Scholar 

  7. R.C. Stephenson, S. Turner and M. Whale, The mean stiffness of thermoplastic composites, Composites, 10: 153 (1979).

    Article  CAS  Google Scholar 

  8. M.W. Darlington and G.R. Smith, Design data for stiffness in short fibre reinforced thermoplastics, in. “Fibre Reinforced Materials: Design and Engineering Applications”, Proceedings of Conference at Inst. Civil Eng., UK, March, 1977, Inst. Civil Engineers, London (1977).

    Google Scholar 

  9. M.W. Darlington and P.L. McGinley, Fibre orientation distribution in short fibre reinforced thermoplastics, J. Mater. Sci., 10: 906 (1975).

    Article  CAS  Google Scholar 

  10. M.W. Darlington, P.L. McGinley and G.R. Smith, Creep anisotropy and structure in short fibre reinforced thermoplastics: Part 1, Prediction of 100 sec. creep modulus at small strains, Plastics and Rubber: Materials and Applications, 2: 51 (1977).

    CAS  Google Scholar 

  11. G.R. Smith, M.W. Darlington and D. McCammond, Flexural anisotropy of glass fibre reinforced thermoplastics injection mouldings, J. Strain Analysis, 13: 221 (1978).

    Article  Google Scholar 

  12. M.A. Christie, M.W. Darlington, D. McCammond and G.R. Smith, Shear anisotropy of short glass fibre reinforced thermoplastics injection mouldings, Fibre Sci. and Tech., 12: 167 (1979).

    Article  Google Scholar 

  13. J.C. Halpin and N.J. Pagano, The laminate approximation for randomly oriented fibrous composites, J. Comp. Mat., 3: 720 (1969).

    Google Scholar 

  14. J.L. Kardos, Structure property relations in short fibre reinforced plastics, CRC Critical Reviews in Solid State Sciences, 3; 419 (1973).

    Article  Google Scholar 

  15. G.R. Smith, Creep anisotropy in short glass fibre reinforced thermoplastics, Ph.D. Thesis, Cranfield Institute of Technology (1976).

    Google Scholar 

  16. H.L. Cox, The elasticity and strength of paper and other fibrous materials, British J. Appl. Phys., 3: 72 (1952).

    Article  Google Scholar 

  17. H. Krenchel, “Fibre Reinforcement”, Akademisk Forlag, Copenhagen (1964).

    Google Scholar 

  18. J.C. Halpin, K. Jerina and J.M. Whitney, The laminate analogy for 2 and 3 dimensional composite materials, J. Comp. Mat., 5: 36 (1971).

    Article  CAS  Google Scholar 

  19. J.E. Ashton, J.C. Halpin and P.H. Petit, “Primer on Composite Analysis”, Technomic Publishing Co., Stamford, Conn. (1969).

    Google Scholar 

  20. L. Nicolais, Mechanics of composites, Poly. Eng. and Sci., 15; 137 (1975).

    Article  CAS  Google Scholar 

  21. T.W. Chou and A. Kelly, Mechanical properties of composites, Ann. Rev. Mater. Sci., 10; 229 (1980).

    Article  Google Scholar 

  22. T.S. Chow, Review — The effect of particle shape on the mechanical properties of filled polymers, J. Mater. Sci., 15: 1873 (1980).

    Article  CAS  Google Scholar 

  23. J.C. Halpin and J.L. Kardos, The Halpin-Tsai equations; a review, Poly. Eng. and Sci., 16: 344 (1976).

    Article  CAS  Google Scholar 

  24. R.A. Schapery, Viscoelastic behaviour and analysis of composite materials, in: “Composite Materials, vol,2, Mechanics of Composite Materials”, G.P. Sendeckyi, ed., Academic Press, New York (1974).

    Google Scholar 

  25. J.C. Halpin, Stiffness and expansion estimates for oriented short fibre composites, J. Comp. Mat., 3: 732 (1969).

    Google Scholar 

  26. M.A. Christie and M.W. Darlington, Creep anisotropy in short fibre reinforced thermoplastics, Proceedings of Third International Conference on Composite Materials, Paris, August 1980, published in “Advances in Composite Materials”, A.R. Bunsell, C. Bathias, A. Martrenchar, D. Menkes and G. Verchery, eds., Pergammon Press, Oxford (1980).

    Google Scholar 

  27. R.M Ogorkiewicz and G.W. Weidmann, Tensile stiffness of a thermoplastic reinforced with glass fibres or spheres, J. Mech, Engineering Sci., 16: 10 (1974).

    Article  Google Scholar 

  28. V.J. Counto, The effect of the elastic modulus of the aggregate on the elastic modulus, creep and creep recovery of concrete, Mag. Concrete Res., 16: 129 (1964).

    Google Scholar 

  29. N. Laws and R. McLaughlin, The effect of fibre length on the overall moduli of composite materials, J. Mech. Phys. Solids, 27: 1 (1979).

    Article  Google Scholar 

  30. M.W. Darlington and D.W. Saunders, Anisotropic creep behaviour Chapter 10 in “Structure and Properties of Oriented Polymers”, I.M. Ward, ed., Applied Science Publishers, London (1975).

    Google Scholar 

  31. British Standard, BS 4618, Recommendations for the presentation of plastics design data, Parts 1.1 and 1.1.1, (1970).

    Google Scholar 

  32. D.A. Thomas and S. Turner, Experimental technique in uniaxial tensile creep testing, in “Testing of Polymers”, volume 4, W.E. Brown, ed., Interscience, New York (1969).

    Google Scholar 

  33. M.A. Christie and M.W. Darlington, Tensile creep of polyamide 6, Plastics and Polymers, 43: 149 (1975).

    CAS  Google Scholar 

  34. C.M.R. Dunn and S. Turner, Thermal history and mechanical properties, Polymer, 15: 451 (1974).

    Article  CAS  Google Scholar 

  35. J.W. Ballard and M.W. Darlington, Shear and tensile creep of thermoplastics at finite strains, Brit. Polymer J., 10: 79 (1978).

    Article  CAS  Google Scholar 

  36. R.E. Lowrie, Glass fibres for high strength composites, in; !,Modern Composite Materials”, L.J. Broutman and R.H. Krock, eds., Addison-Wesley, Reading, Mass. (1967).

    Google Scholar 

  37. T.W. Chou, S. Nomura and M. Taya, A self-consistent approach to the elastic stiffness of short fibre composites, J. Comp. Mat., 14: 178 (1980).

    Article  Google Scholar 

  38. S. Turner, Deformation data for engineering design, in: “Testing of Polymers”, volume 4, W.E. Brown, ed., Interscience, New York (1969).

    Google Scholar 

  39. L.C. Cessna, J.B. Thomson and R.D. Hanna, Chemically coupled glass-reinforced polypropylene, SPE Journal, 25; 35 (1969).

    CAS  Google Scholar 

  40. L.C. Cessna, Cyclic creep test data for GR polypropylene, SPE Journal, 28: 28 (1972).

    CAS  Google Scholar 

  41. F. Polato, P. Parrini and G. Gianotti, A new technique for the measurement of glass fibre orientation in composite materials, Proceedings of Third International Conference on Composite Materials, Paris, August, 1980, published in “Advances in Composite Materials”, A.R. Bunsell, C. Bathias, A. Martrenchar, D. Menkes and G. Verchery, ed., Pergammon Press, Oxford (1980).

    Google Scholar 

  42. W.M. Speri and C.F. Jenkins, Effect of fibre-matrix adhesion on the properties of short fibre reinforced ABS, Poly. Eng and Sci., 13: 409 (1973).

    Article  CAS  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Editor information

Editors and Affiliations

Rights and permissions

Reprints and permissions

Copyright information

© 1983 Plenum Press, New York

About this chapter

Cite this chapter

Darlington, M.W., Christie, M.A. (1983). Time Dependent Properties of Injection Moulded Composites. In: Seferis, J.C., Nicolais, L. (eds) The Role of the Polymeric Matrix in the Processing and Structural Properties Composite Materials. Springer, Boston, MA. https://doi.org/10.1007/978-1-4615-9293-8_18

Download citation

  • DOI: https://doi.org/10.1007/978-1-4615-9293-8_18

  • Publisher Name: Springer, Boston, MA

  • Print ISBN: 978-1-4615-9295-2

  • Online ISBN: 978-1-4615-9293-8

  • eBook Packages: Springer Book Archive

Publish with us

Policies and ethics