Abstract:
Nowadays, research in automotive and construction industries focuses on
materials that offer low density along with superior dynamic and static performance.
This goal has led to increasing use of composites in general, and carbon fibre (CF)
composites in particular. CF composites have been adopted widely in the space
industry and motorsports. However, their high stiffness and low density leads to low
damping performance, which is responsible for increased levels of noise and
reduction in service life. On the other hand, natural fibres (NF) like flax fibres (FF) are
capable of delivering a much better damping performance. A hybrid composite
comprising of FF and CF can potentially deliver both on strength and higher damping
performance.
In this study the mechanical and damping properties of CF, FF and their hybrid
composites were examined. Composites' anisotropic nature affects their response to
vibrations and so traditional damping experimental setups used for metals had to be
ruled out. A damping set up based on Centre Impedance Method (CIM) was adopted
for the purpose of this study which was based on an ISO standard originally
developed for glass laminates. Standard tensile and flexural tests were conducted in
order to characterise the performance of the hybrid composite. The experimental
work was accompanied by finite elements analysis (FEA). The experimental data and
FEA were used to optimize the hybrid structure layup with respect to damping and
structural response.
