P. Lassince, Kaiser Aluminum, Spokane, WA; T. Warner, F. Eberl, J. C. Ehrstrom, Alcan, Voreppe, France; P. Lequeu, H. Ribes, ALCAN Pechiney Rhenalu, Issoire, France
Meeting ambitious airframer targets for weight and cost reduction will require both materials’ development efforts and innovative processing and design solutions. Alcan Aerospace is actively pursuing both routes.
To achieve optimum weight and cost benefits when developing new solutions for airframe parts, it is necessary to consider concomitantly their design, the corresponding materials, as well as appropriate joining/forming techniques. This multidisciplinary approach implies the development of concepts optimised at the level of the part: e.g. consider wing covers rather than the wing panel and wing stringer separately. It also involves developing solutions that enable the tailoring of materials’ properties to local requirements at an acceptable cost: in this context welding (both FSW and LBW) has great potential, but other innovative approaches are possible.
Within such a holistic approach, there is still significant potential for materials’ development, not least to optimise property balances for the chosen design/joining/forming solutions. Even in apparently well-explored alloy systems such as the 7xxx family, products with improved damage tolerance-strength balances have recently been developed: 7056-T7951 (for high strength, high damage tolerance upper wing skins) and 7140-T7651 (for thick plate applications). Higher performance Al-Cu-Mg alloys are also available, such as 2139-T8 (Al-Cu-Mg-Ag alloy) and 2023-T3x (Al-Cu-Mg-Zr-Sc). More damage tolerant variants of another family of alloys, the so-called “third generation Al-Li alloys” initially largely developed for military and space applications, are also in the final stages of development.
Examples of solutions combining design-materials-joining technique will be presented, with particular emphasis on the corresponding implications for material and processing optimisation.
Summary: Meeting ambitious airframer targets for weight and cost reduction will require both materials’ development efforts and innovative processing and design solutions. Alcan Aerospace is actively pursuing both routes.
To achieve optimum weight and cost benefits when developing new solutions for airframe parts, it is necessary to consider concomitantly their design, the corresponding materials, as well as appropriate joining/forming techniques. This multidisciplinary approach implies the development of concepts optimised at the level of the part: e.g. consider wing covers rather than the wing panel and wing stringer separately. It also involves developing solutions that enable the tailoring of materials’ properties to local requirements at an acceptable cost: in this context welding (both FSW and LBW) has great potential, but other innovative approaches are possible.
Examples of solutions combining design-materials-joining technique will be presented, with particular emphasis on the corresponding implications for material and processing optimisation.