Improvement of rCF behaviour through the introduction of NF

The use of recycled carbon fibres (rCF) allows for reduction of emissions impacting energy and resource requirements. A major drawback of using rCF composites is the discontinuous nature of the fibres as this limits the performance and applications. The present investigation aimed to overcome some of these limitations by manufacturing hybrid composites by combining rCF and natural fibres (NF). One of the key observations was a significant change in the failure mode of hybrid samples under various loading scenarios, where the composite did not shatter but rather failed in a controlled manner. Initial results also showed an overall improvement impact properties in comparison to plain rCF. Similar performance was observed in other tests. Research was focused on determining the most effective ply sequencing under different types of loading and understanding the effect of the ply sequence on the failure mechanisms. It was determined that depending on the application, the layups does effect the performance of the composite. Composites with rCF core and NF skin proved to be the most optimal in bending and in tension, whereas other layups favoured one of the two conditions. During impact tests, the layup sequencing did not have a significant effect on the energy dissipation, however, reinforcing rCF with NF did show a significant improvement. The composite has been manufacturing via a cold cure compression moulding technique, with the matrix being bio-based epoxy resin. Due to high pressure applied, the volume of resin within the mould managed to be reduced to minimum required. No coupling agent were required.