Dynamic Mode II Delamination in Through Thickness Reinforced Composites

  • Mehdi Yasaee
  • Galal Mohamed
  • Antonio Pellegrino
  • Nik Petrinic
  • Stephen R. Hallett
Conference paper
Part of the Conference Proceedings of the Society for Experimental Mechanics Series book series (CPSEMS)

Abstract

Through thickness reinforcement (TTR) technologies have been shown to provide effective delamination resistance for laminated composite materials. The addition of this reinforcement allows for the design of highly damage tolerant composite structures, specifically when subjected to impact events. The aim of this investigation was to understand the delamination resistance of Z-pinned composites when subjected to increasing strain rates.

Z-pinned laminated composites were manufactured and tested using three point end notched flexure (3ENF) specimens subjected to increasing loading rates from quasi-static (~0 m/s) to high velocity impact (5 m/s), using a range of test equipment including drop weight impact tower and a split Hopkinson bar (SHPB).

Using a high speed impact camera and frame by frame pixel tracking of the strain rates, delamination velocities as well as the apparent fracture toughness of the Z-pinned laminates were measured and analysed. Experimental results indicate that there is a transition in the failure morphology of the Z-pinned laminates from quasi-static to high strain rates. The fundamental physical mechanisms that generate this transition are discussed.

Keywords

Through thickness reinforcement Damage tolerance Delamination testing Z-pins Strain rate Impact 

Notes

Acknowledgements

The authors would like to acknowledge Rolls-Royce plc for their support of this research through the Composites University Technology Centre (UTC) at the University of Bristol, UK.

References

  1. 1.
    Yasaee, M., Mohamed, G., Allegri, G., Hallett, SR.: Delamination resistance of through thickness reinforced composites. In: Proceedings of the 16th European Conference on Composite Materials, Seville (2014)Google Scholar
  2. 2.
    Partridge, I.K., Yasaee, M., Allegri, G., Lander, J.K.: Damage-tolerant composite structures by Z-pinning. In: Toughening mechanisms in composite materials, pp. 161–189. Elsevier, Burlington (2015). doi:10.1016/B978-1-78242-279-2.00006-8
  3. 3.
    Lenzi, F., Riccio, A., Clarke, A., Creemers, R.: Coupon tests on z-pinned and unpinned composite samples for damage resistant applications. Macromol. Symp. 247, 230–237 (2007)CrossRefGoogle Scholar
  4. 4.
    Partridge, I.K., Cartie, D.D.R.: Delamination resistant laminates by Z-Fiber pinning: part I manufacture and fracture performance. Compos. A: Appl. Sci. Manuf. 36(1), 55–64 (2005)CrossRefGoogle Scholar
  5. 5.
    Pegorin, F., Pingkarawat, K., Mouritz, A.P.: Comparative study of the mode I and mode II delamination fatigue properties of z-pinned aircraft composites. Mater. Des. 65, 139–146 (2014)CrossRefGoogle Scholar
  6. 6.
    Colin de Verdiere, M., Skordos, A.A., Walton, A.C., May, M.: Influence of loading rate on the delamination response of untufted and tufted carbon epoxy non-crimp fabric composites/Mode II. Eng. Fract. Mech. 96, 1–10 (2012)CrossRefGoogle Scholar
  7. 7.
    Liu, H., Yan, W., Yu, X., Mai, Y.: Experimental study on effect of loading rate on mode I delamination of z-pin reinforced laminates. Compos. Sci. Technol. 67(7–8), 1294–1301 (2007)CrossRefGoogle Scholar
  8. 8.
    Schlueter, A., Parab, N.D., Chen, W.: Loading rate effects on mode I delamination of Z-pinned composite laminates. In: Song, B., Casem, D., Kimberley, J. (eds.) Dynamic Behavior of Materials, Volume 1. Springer, Cham (2014)Google Scholar
  9. 9.
    ASTM-D7905-14. Standard test method for determination of the mode II interlaminar fracture toughness of unidirectional fiber-reinforced polymer matrix composites. ASTM Int. (2014)Google Scholar
  10. 10.
    ASTM D790-07. Standard test methods for flexural properties of unreinforced and reinforced plastics and electrical insulating materials. ASTM Int. 2007e1 (2007)Google Scholar
  11. 11.
    Hallett, S.R.: Three-point beam impact tests on T300/914 carbon-fibre composites. Compos. Sci. Technol. 60(1), 115–124 (2000)MathSciNetCrossRefGoogle Scholar
  12. 12.
    Blackman, B.R.K., Dear, J.P., Kinloch, A.J., Macgillivray, H., Wang, Y., Williams, J.G., Yayla, P.: The failure of fibre composites and adhesively bonded fibre composites under high rates of test—part I mode I loading-experimental studies. J. Mater. Sci. 30, 5885–5900 (1995)CrossRefGoogle Scholar
  13. 13.
    Weeks, C.A., Sun, C.T.: Modeling non-linear rate-dependent behavior in fiber-reinforced composites. Compos. Sci. Technol. 58(3–4), 603–611 (1998)CrossRefGoogle Scholar
  14. 14.
    de Moura, M.F.S.F., de Morais, A.B.: Equivalent crack based analyses of ENF and ELS tests. Eng. Fract. Mech. 75, 2584–2596 (2008)CrossRefGoogle Scholar
  15. 15.
    Wang, Y., Williams, J.G.: Corrections for mode II fracture toughness specimens of composites materials. Compos. Sci. Technol. 43(3), 251–256 (1992)CrossRefGoogle Scholar
  16. 16.
    Pegorin, F., Pingkarawat, K., Daynes, S., Mouritz, A.P.: Mode II interlaminar fatigue properties of z-pinned carbon fibre reinforced epoxy composites. Compos. A: Appl. Sci. Manuf. 67, 8–15 (2014). doi:10.1016/j.compositesa.2014.08.008 CrossRefGoogle Scholar
  17. 17.
    Cartie, D.D.R., Troulis, M., Partridge, I.K.: Delamination of Z-pinned carbon fibre reinforced laminates. Compos. Sci. Technol. 66, 855–861 (2006)CrossRefGoogle Scholar
  18. 18.
    Compston, P., Jar, P.-Y.B., Burchill, P.J., Takahashi, K.: The effect of matrix toughness and loading rate on the mode-II interlaminar fracture toughness of glass-fibre/vinyl-ester composites. Compos. Sci. Technol. 61(2), 321–333 (2001)CrossRefGoogle Scholar

Copyright information

© The Society for Experimental Mechanics, Inc. 2017

Authors and Affiliations

  • Mehdi Yasaee
    • 1
  • Galal Mohamed
    • 2
  • Antonio Pellegrino
    • 3
  • Nik Petrinic
    • 3
  • Stephen R. Hallett
    • 2
  1. 1.School of Aerospace, Transport and ManufacturingUniversity of CranfieldCranfieldUK
  2. 2.Advanced Composites Centre for Innovation and Science (ACCIS)University of Bristol, Aerospace EngineeringBristolUK
  3. 3.Department of Engineering Science, Engineering and Technology BuildingOxford UniversityOxfordUK

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