New components for safer and more secure aircraft composite materials Conventional aircraft structures employ a number of protective materials and monitoring systems for a variety of jobs. An EU initiative introduced multifunctional components integrating tasks for lighter and safer aircraft. Digital Economy Transport and Mobility Industrial Technologies Fundamental Research © Forance, Shutterstock The aircraft industry increasingly uses composite materials due to their enhanced strength and light weight. In addition, they can be formed into complex shapes more aerodynamically efficient than metals. However, they are poor conductors of heat (or cold) and electricity. As a result, they can burn easily, releasing toxic gases and smoke and, conversely, enable ice formation. Ice protection is usually accomplished with a metal mesh or foil integrated into the structure, whereas fire protection is performed with thermal barrier coatings. The EU-funded LAYSA (Multifunctional layers for safer aircraft composites structures) project developed a new layer providing both ice and fire protection, as well as structural health monitoring. Work began with the definition of end user specifications, followed by the preparation and characterisation of different nanomaterial formulations and combinations. In order to produce the selected prototypes, the LAYSA team prepared and supplied these needed raw materials, namely nano-reinforcement dispersions, nano-doped resin films and buckypapers (thin sheets of carbon nanotubes). Project partners predicted the electrothermal behaviour, mechanical response and sensing performance of nano-reinforced polymer material systems. This was done by incorporating relationships between nanoscale structures and macro-scale properties into multi-scale models. They also considered modelling with respect to the fire burn-through response of a composite panel. Once the most promising materials and processes were identified, scientists optimised the multifunctional concept and manufacturing process. Two demonstrators were manufactured to validate processes. They undertook thorough trials and assessment of the demonstrators and prototypes. Lastly, a technical and commercial evaluation of the products was performed to evaluate potential for transfer to industrial applications. LAYSA efforts should deliver high-performance multifunctional aircraft structures based on novel nanocomposites with exceptional thermal and electrical conductivity and sensing capacity. The structural elements will enable thermal protection and structural health monitoring in one system for safer, lighter planes with lower fuel and power consumption. Keywords Aircraft, composite materials, LAYSA, ice and fire protection, structural health monitoring, buckypapers
