Low-Velocity Impact and Compression-After-Impact Behaviour of Flax Fibre-Reinforced Composites

Abstract

This study details the low-velocity impact and compression-after-impact (CAI) behaviour of flax fibre-reinforced polymer (FFRP) composites. The impact resistance, energy absorption efficiency and residual compressive strength as well as the damage pattern of the FFRP composites are compared with the corresponding features of glass fibre-reinforced polymer (GFRP) composites, and the effect of the stacking sequence of FFRP composites is also investigated. The results show that the cross-ply FFRP composites have the highest impact resistance, whereas the multi-directional ply composites have the lowest impact resistance but the highest energy absorption efficiency. The energy absorption efficiency of the FFRP composites is greater than that of the GFRP composites, but the penetration resistance and residual compressive strength of the FFRP composites are lower than those of the GFRP composites with the same stacking sequence, mainly due to the lower tensile strength and elongation at fracture of the FFRP composites. It is also reported that the damage pattern of the FFRP composites is localised cracking and delamination, unlike the overall delamination failure exhibited in the GFRP composites after CAI testing. Finally, the failure mechanisms of the FFRP and GFRP composites are detailed.