Journal of Materials Science

, Volume 27, Issue 14, pp 3969–3976 | Cite as

Measurement and analysis of the fracture of a liquid crystal polymer

  • J. Sweeney
  • B. Brew
  • R. A. Duckett
  • I. M. Ward


The fracture initiation behaviour of injection-moulded plaques of a liquid-crystal polymer is described. Attention is restricted to cracks in the plane of the plaques propagating along the mould fill direction. The material is both anisotropic and inhomogeneous; the latter factor is accommodated by adopting a skin-core model of the plaque structure. The inhomogeneity leads to mixed mode (Modes I and II) fracture in some cases, and both single and mixedmode testing is used. The results can be represented in terms of either stress intensity or strain energy release rate by simple mixed-mode failure criteria.


Stress Intensity Liquid Crystal Energy Release Failure Criterion Energy Release Rate 
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Copyright information

© Chapman & Hall 1992

Authors and Affiliations

  • J. Sweeney
    • 1
  • B. Brew
    • 1
  • R. A. Duckett
    • 1
  • I. M. Ward
    • 1
  1. 1.IRC in Polymer Science and TechnologyUniversity of LeedsLeedsUK

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