A. P. Vloemans, J. J. M. de Rijck, Corus Research Development & Technology, IJmuiden, Netherlands; M. Miermeister, Aleris Aluminum Koblenz GmbH, Koblenz, Germany

Summary: For aerospace applications, new versions and derivates of aluminium aerospace alloys were developed within Corus Aluminium Rolled Products together with Corus Research, Development & Technology. These alloys were designed to achieve better properties in terms of static strength, damage tolerance and corrosion. Some of them show to be weldable by means of laser welding and friction stir welding. This enables an improved joining method, in terms of performance and cost, to assemble, in example, skin sheets, stringers and clips together to form fuselage panels. To study the influence of these newly developed aluminium alloys on the damage tolerant behavior of a fuselage panel, both the material properties as well as the structural stress field in the component need to be known. A finite element model was generated that represents a typical stiffened panel in the fuselage of a commercial airplane. The model comprises the description of the skin sheet, stringers and frames and enables the calculation of the load distribution over the considered fuselage panel, expressed in terms of nodal forces, bending moments and stresses. In this way the stress critical locations in the fuselage panel part concerning damage tolerance can be found. Successively, a series of damage tolerant analysis tools were selected to be used for a next analysis step to investigate the fatigue crack initiation, the fatigue crack growth and the residual strength of the considered panel. As a result the lifetime of the fuselage panel can be assessed. This analysis approach allows the evaluation of the potential of new aluminium alloys to achieve improved performance of aircraft structures in terms of weight saving.