Nanomaterials to enhance aircraft composite parts The aerospace industry is the foremost adopter of advanced composite materials, but for all their incredible promise, composites are expensive to produce and very prone to damage. EU-funded scientists added carbon nanomaterials to the polymer matrix to increase strength and toughness. Industrial Technologies © Thinkstock Polymer nanocomposites are a new class of composite materials that have attracted a great deal of attention in research labs and industry. The unique and extraordinary electrical, mechanical and thermal properties of carbon nanotubes (CNTs) and graphene render them attractive fillers for reinforcing polymers to form high-performance materials. By incorporating nanomaterials into carbon fibre-reinforced plastics (CFRPs), researchers within the CARHAY2011 (Design, manufacturing and impact testing of advanced composite materials) project observed a 50 % increase in compression-after-impact (CAI) strength in comparison with conventional CFRPs. Furthermore, the resulting materials demonstrated improved fracture strength and compression. Adding nanomaterials to improve CFRP performance is particularly effective when optimising filler dispersion and interfacial interaction within the polymer matrix. Conventional methods of optimising dispersion have so far included the use of strong acid solutions and ultrasounds, which do not allow for scalable production and can possibly damage nanocarbons. However, the CARHAY2011 team used an innovative plasma treatment process that allowed them to control the amount and type of imparted changes in the filler surface properties. This new surface modification process is scalable and energy efficient. By using resin infusion, researchers successfully demonstrated and tested full-scale stiffened panels (0.9 x 0.6 m2). Large batches of resins were produced (up to 10 kg) with CNT and graphene fillers. Furthermore, the team demonstrated that it is possible to manufacture a panel incorporating stiffeners in a single-shot process, resulting in more lightweight and lower-cost structures. Improvement in the CAI strength of composite materials by adding carbon nanomaterials leads to weight reductions that translate to decreases in fuel consumption and associated emissions. Project results were disseminated through a press release, a poster and two publications. Keywords Aircraft, composite materials, carbon nanotubes, graphene, resin infusion
