Characterisation of Highly-Aligned, Discontinuous, Fibre Composites for Compressive Performance

A new generation of advanced composites, featuring three dimensional architectures which mimic the multi-scale reinforcement seen in biological composite materials such as bone and wood are currently being developed. As with their natural antecedents, these novel manufactured materials are being designed to incorporate hierarchical systems of discrete structural elements which couple mechanistic properties across length scales. The aim of this programme of research is to significantly improve the compressive load bearing characteristics of reinforced polymeric composite materials.

Highly aligned, discontinuous carbon-fibre composite tapes promise to be useful structural elements across both meso- and macro-levels within the architectures being considered. The high alignment of the fibres can allow mechanical properties comparable to continuous fibre tapes, whilst the intrinsic pliability of the tapes favours the formation of complex structural geometries. This paper presents a discussion of the challenges encountered in characterising these materials in compression using a novel four-point bending test, and outlines the remedial actions taken.