Eco-composites

Kurzfassung

Composite materials currently used in aviation have one thing in common: they are man-made and especially the carbon fibres are very energy intensive in the production. Renewable materials like bio-fibres (e.g. flax) and bio-resins are under investigation for a long time for their use in composites but they did not made it into a modern aircraft in high amounts yet. As safety is of primary importance in aviation, the lack of experience in the long-term performance of composites made of renewable materials is still an obstacle for their usage. It is therefore currently out of scope to substitute high performance and safety-relevant structural parts of the aircraft with bio-sourced materials. On the other side, interior parts and secondary structures which are not stressed on such high levels offer possible areas of application. When replacing state of the art materials like glass fibre reinforced phenolic resins it must be ensured to fulfil the high safety standards. Contrary to glass fibres the lignocellulosic natural fibres are flammable and susceptible to humidity. Therefore special provisions must be taken into account to protect bio-composites from fire and environmental influence. On the other side bio-resins with promising characteristics could substitute phenolic resins. The presentation will show possible applications of eco-materials and give an overview of obstacles and challenges by the special conditions in aviation. Fire properties of bio-composites with examples of recent results at DLR and suggestions for research topics in future projects will be presented.