Investigation into the fatigue properties of flax fibre vinyl-ester composites and hybrid composites based on flax and glass fibres

Natural fibre reinforced composites (NFRC) offer a sustainable and environmentally friendly alternative to composites made from synthetic polymers. However, industry remains reluctant on the adoption of NFRC in load-bearing components due various issues related to variability, moisture absorption, weak interfacial bonding and inferior mechanical performance compared to their synthetic fibre reinforced composites. However, recent developments in NFRC are making them more attractive for use in applications subjected to dynamic loading. As many engineering components functioning under dynamic loading tend to fail in a more catastrophic manner under fatigue-related mechanisms, determining the fatigue life and performance of natural fibre composites is of crucial importance, provided that research on the fatigue behaviour of these materials is still limited. The current work aims to study the fatigue response of flax fibre composites and their hybrid alternatives with glass fibres and produce robust results that can motivate the adoption of NFRC in load bearing applications. Three different batches of specimens based on flax fibre, and glass fibre composites along with flax-glass hybrid composites will be investigated. The composite materials will be fully characterized by conducting all the necessary mechanical testing to extract their mechanical and physical properties. Then, the fatigue resistance behaviour will be studied by correlating various parameters and it will be compared for each batch of specimens. Various NDT methods, such as X-ray computed tomography, will be employed at different stages of the testing to monitor and assess the damage mechanisms developed in the material.