AEROMAT 2004 – Proposed Abstract Development of high strength alloys for fuselage and wing applications F. Eberl, J. Boselli, T. Warner, Pechiney R&D Center, Voreppe, France R. Dif, Pechiney Rhenalu, Issoire, France F. Heymes, Pechiney Aviatube, Issoire, France S. Jambu, Pechiney Aviatube, Montreuil-Juigné, France In order to further reduce weight on new or enhanced aircraft, the improvement of static strength properties of Aluminium alloys is of great interest. The increase of the solute content within the 7xxx Aluminium family enables an increase of the yield strength to levels higher than 100 ksi. The optimization of the major alloying element additions (Zinc, Copper and Magnesium), both in terms of total solute level and in terms of balance, leads to a very high strength solution for extruded fuselage sections and high strength upper wing applications whilst maintaining appropriate toughness properties. The high properties are achieved by a combination of precipitation hardening and a contribution of the unrecrystallized fibrous grain structure. The corrosion performance depends strongly on aging practice for these near-peak tempers. Fatigue performance is related to a number of metallurgical parameters, including strength, degree of overage, purity levels, etc. Laboratory and industrial data illustrating the metallurgical principles underlying these properties will be discussed. Detailed property balances for these strength-dominated products aimed at extruded fuselage stringers and top wing plates and extrusions will be presented. Authors: F. Eberl, Research Eng, Aerospace, Pechiney CRV, 38340 Voreppe, France Ph: (33)-4-76-57-84-24 Fax: (33)-4-76-57-80-99 e-mail: frank.eberl@pechiney.com J. Boselli, Research Eng, Aerospace, Pechiney CRV, 38340 Voreppe, France Ph: (33)-4-76-57-84-24 Fax: (33)-4-76-57-80-99 e-mail: julien.boselli@pechiney.com T. Warner, Deputy Head of Aerospace Technical Products, Pechiney CRV, 38340 Voreppe, France Ph: (33)-4-76-57-81-51 Fax: (33)-4-76-57-80-99 e-mail: timothy.warner@pechiney.com R. Dif, Technical development eng., Pechiney Rhenalu, 63502 Issoire Cedex, France Fax: (33)-4-73-55-51-27 e-mail: ronan.dif@pechiney.com F. Heymes, Heavy Extrusions R&D Manager., Pechiney Aviatube, 63502 Issoire Cedex, France Ph: (33-4-73-55-52-75 Fax: (33)-4-73-55-51-27 e-mail : fabrice.heymes@pechiney.com S. Jambu, Technical development Eng, Pechiney Aviatube, 49460 Montreuil-Juigné, France Ph: (33)-2-41-37-44-64 Fax: (33)-2-41-37-44-99 e-mail: stephane.jambu@pechiney.com