Abstract
The objective of this study was to investigate strain-rate dependent energy absorption mechanisms during interlaminar fracture of thermosetting (epoxy) and thermoplastic (PEEK) uni directional carbon fibre (CF) composites. A simple model addressing the translation of matrix toughness to mode I and mode II interlaminar toughness of the composite is presented, in conjunction with a fractographic examination of the fracture surfaces and the fracture process. The observed rate dependency of composite fracture toughness is attributed to the rate dependent toughness of the viscoelastic matrix and the size of the process zone around the crack tip. Other important factors identified are the roughness of the fracture surface and fibre bridging.
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Friedrich, K., Walter, R., Carlsson, L.A. et al. Mechanisms for rate effects on interlaminar fracture toughness of carbon/epoxy and carbon/PEEK composites. J Mater Sci 24, 3387–3398 (1989). https://doi.org/10.1007/BF01139070
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DOI: https://doi.org/10.1007/BF01139070