Picture of the month: Recyclable and flexible fibre-reinforced plastics for aircraft construction

The image shows a demonstrator of an unconventional, bionic stiffening structure for an aircraft fuselage. The outer skin is visible at the bottom, with stiffeners on top. Instead of the stringers and spars that form the load-bearing framework of an aircraft, foam cores are attached to which stress-optimised profiles are laid using automated fibre placement (AFP).

Versteifungsstruktur eines Flugzeugrumpfes. Bildnachweis: Dr. Carsten Schmidt/LUH

Automated fibre placement (AFP) is an automated manufacturing process for composite components, especially complex shapes, in which individual fibre tapes are precisely applied to a mould surface using a robot system. It is used to produce lightweight, high-strength composite structures.

The photo of this innovative fuselage design was taken as part of the ‘Flexible Technologies for the Production of Customised CFRP Structures – FlexProCFK’ project, a collaboration between the Technische Universität Braunschweig, Leibniz University Hannover and Clausthal University of Technology. The researchers’ goal is to develop an innovative, flexible manufacturing technology for the production of customised CFRP structures. The construction method forms the basis for current research projects such as ‘reFrame’.

In the ‘reFrame’ project, researchers from Hanover, Braunschweig, Clausthal and Göttingen are working on processing carbon fibre-reinforced plastics so that they can be reused in aircraft construction. This is because recycling them poses a challenge – until now, the recovered materials could not be used for safety-critical applications. The aim is to enable a closed carbon fibre recycling loop while maintaining the high-performance potential of carbon fibres. The background to this is that no loss of performance can be accepted in such high-performance components, as this would increase the structural weight and thus, for example, the fuel consumption of aircraft.