Effect of Incipient Heat Damage on the Fatigue Properties of Aircraft Composites

Abstract:

This paper presents a preliminary investigation into the effect of incipient heat damage on the mechanical properties of a carbon-epoxy composite. Specimens were exposed to a range of temperatures varying from 0°C to 280°C for one hour and then tested to quantify the effects of this high temperature exposure on the short-beam shear, Mode I and II interlaminar fracture toughness, and the Mode I fatigue properties. The results showed that as the exposure temperature increased, the short-beam shear suffered a reduction, whereas the Mode I and Mode II fracture toughness increased after an initial reduction. The fatigue disbond growth rates were largely un-affected under heat exposure below 280°C. This complex behaviour in the degradation in fracture toughness is likely due to the increased fibre bridging brought about by the reduction in matrix strength.

• Periodical: Advanced Materials Research (Volumes 891-892)
• Pages: 1810-1815
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.891-892.1810
• Online since: March 2014
• Authors: Rachel Ong, Chun H. Wang*
• Keywords: Aircraft, Composite, Fatigue, Heat Damage

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