The CAPCOM project, funded by Airbus, has been established to investigate the viability of plant-based products for use in the production of composites designed for aircraft interior panels. The project, which was inspired by the Airbus Fly You Ideas Competition, focuses specifically on the design and manufacture of a composite with both fibre and matrix components being sourced from the castor plant, with the aim of reducing dependence on non-renewable material sources, lowering emissions and improving end-of-life biodegradability of the components (Beehag et al. 2010).
Previous studies have proven successful in the sourcing and extraction of both the fibre and matrix (Nylon PA-11) content for the composite, as well as fibre treatment for the reduction of moisture uptake, and determining mechanical properties of both fibre and matrix. Random fibre orientation composite test samples have been manufactured, resulting in initial data being produced, however the determination of fibre adhesion strength and effects caused by fibre surface treatment have yet to be investigated.
To determine the adhesion strength of the fibre-matrix interface, a suitable test method must first be determined in combination with potential (lab-scale) manufacturing methods. This has been done with a strong focus on repeatability and reliability of the samples, taking into account the multiple challenges associated with natural fibre composites.
It has been decided that a transverse tensile test, with a sample size of 15x40x3mm will be used, and a manufacturing process has been proposed, designed, fabricated and tested. The design uses heat and pressure supplied from an existing hot press to inject the nylon into a mould with the pre-clamped fibres. The mould is sealed with a high temperature o-ring in order to reduce waste while also reducing damage to the fibres during the clamping process.
As castor fibres are difficult and time consuming to obtain, testing the manufacturing method will be performed with a commercially available flax fibre, and later confirmed with castor fibres, which have been found to significantly similar.
The expected outcomes of the project include a lab-scale manufacturing method for the production of uni-directional natural fibre composites, as well as a suitable test method to quantify fibre adhesion strength. It is expected that the project will be continued after this point, and as such suggestions to aid in this will be provided.