Automated Production of an CFRP-Aircraft Side Shell using AFP and Inductive Co-bonding Technology

Abstract

The paper will deal with the work of German Aerospace Center (DLR) within the EU FP 7 project 'Maaximus'. The major aim of the project is to develop highly integrated and precise design methods for aeronautical structures made of Carbon Fiber Reinforced Plastics (CFRP), which allows validating computations with smaller testing samples. With the state of the art design methods, a full scale fuselage barrel is needed for validation. With the new design methods, only a smaller part structure like a side shell is necessary. Thus, the time and costs for testing of physical demonstrators and therefore the overall development-time for a new aircraft is dramatically reduced. A team of researchers at the Center for Lightweight Production Technology (ZLP), Stade, Germany, was responsible for the task 7.6 Production of the full scale demonstrator. For the validator structure an Airbus A 350 like side shell with a pax door was chosen. The project tasks of DLR during manufacturing of the demonstrator will be presented. These include the process steps automated skin layup, manufacturing of all stringers, co-bonding of cured stringers with wet skin and automated production of near net-shaped preforms of the C73-frames. Focus will be put on the quality monitoring system during the production of the side shell skin using Automated Fiber Placement technology (AFP). Methods for the detection and the adjustment of layup-defects like tow-gaps will be discussed. Another focus will be put on the innovative co-bonding technology using inductive heating. The dependencies between process parameters and the properties of the co-bond will be discussed. The paper will close with a presentation of the relevant steps for the fully automated textile preforming process of the z-type C73-frames. An outlook will be given about the potential of the presented technologies for an economic production of aeronautical structures made of CFRP and the challenges which still are to overcome.