Mechanical performance and damage mechanisms of thin rectangular carbon/ Elium® tubular thermoplastic composites under flexure and low-velocity impact

Abstract

Hollow thin composite tubular structures are widely used in many industrial applications and there is a growing need to innovate both the manufacturing process which is suitable for mass production as well as the material aspects to improvise the mechanical properties and the weight. The current research presents a detailed study on manufacturing thin hollow woven carbon fibre (WC)/Elium® (EL) rectangular tubular structures. Bladder resin transfer moulding process optimization study is carried out and the moldability zones were defined. A detailed experimental investigation was carried out to understand the impact and flexure properties of woven carbon (WC) tubular configurations with Elium® (EL) and Epoxy (EP) matrix system. Impact tests were performed at 6 different energies to derive the energy profiling diagrams by studying the penetration and preformation thresholds. WC/EL tubular configuration has shown a maximum 12.5% increase in peak load and 55% increase in absorbed energy as compared to WC/EP composite, respectively. The WC/EL composite tubes have shown similar or better results in terms of bending strength (10% higher) and there was a noticeable increase in deformation owing to the extended plasticity behaviour of acrylic thermoplastic resin compared to WC/EP composites. The rationale and underlying reasons for the differences in the mechanical performance and failure mechanisms for both the tubes tested in impact and flexural are studied with the help of high-speed camera examination and microscopic study and are deliberated in this paper.