Inaugural Lecture of Prof Conchur O Bradaigh: Lightweight Composite Materials, How Far and How Fast?
From Billy Rosendale
Lightweight composite materials, composed of polymers reinforced by advanced fibres made of carbon, glass and polymers, have come a long way since they were first introduced in the US space industry in the 1960s. Today, we have substantially carbon fibre composite passenger aircraft (Boeing Dreamliner, Airbus A-350, Bombardier C-Series), electric/hybrid automobile bodies (BMW i-series), and super yachts with composite masts of more than 90m height. High performance composites are used for the blades of wind and tidal turbines, as well as for human bone and spinal fixation devices. The main drivers for the lightweight composites revolution are the need to increase fuel efficiency and reduce greenhouse-gas emissions in transport, to generate renewable energy more cost-effectively and to increase performance and personal protection in security, defence, sports and leisure applications.
The speed and limits of composites penetration into transport, energy, infrastructure and consumer sectors will depend on development of lower cost, higher-volume manufacturing processes and on improved fire-resistance, repair and end-of-life strategies for these complex materials. There may be limits on the mechanical properties that can be industrially achieved with advanced microscale fibres, while the much-vaunted nanoscale reinforcements (e.g. carbon nanotubes) have so far failed to deliver on their promise of a step-change in strength and stiffness. Lower embodied energy and less reliance on fossil fuels for polymer and fibre feedstocks will also be necessary for long-term sustainability of composite materials.