Aerospace metallic materials technology

Citation

(2006), "Aerospace metallic materials technology", Anti-Corrosion Methods and Materials, Vol. 53 No. 5. https://doi.org/10.1108/acmm.2006.12853eab.001

Aerospace metallic materials technology

Aerospace metallic materials technology

Keywords: Aerospace industry, Aircraft components, Alloys

The 2006 ASM AeroMat Seattle Conference served as a forum for aerospace aluminum producers to present the latest advances in metallic materials technology. In particular, Alcan Aerospace continued a long tradition by actively participating with a total of eight presentations covering the full spectrum of new aluminum alloys, applications, and novel joining technologies. Eight aerospace specialists representing Alcan's Ravenswood, Issoire facilities as well as R&D Center in Voreppe participated in the proceedings.

Philippe Lassince, R&D Director of the Aerospace, Transportation, and Industry Division of the Alcan group highlighted its contribution to advanced aluminum solutions developed in closed partnership with OEM's. He showed that standard and third generation lithium-containing alloys continue to have a significant potential for improvement in the key design properties, successfully competing with composite designs. Solutions involving laser beam welding (LBW), friction stir welding (FSW), and age-forming illustrated the multi-disciplinary approach adopted by Alcan a number of years ago. Citing these fabrication methods, authors demonstrated several very promising applications of the “locally tailored properties” concept, proving that by breaking free from the “tyranny of the property balance” metallurgical paradigm, significant improvements are possible for advanced metallic materials.

Dr Philippe Lequeu, R&D Manager at the Issoire plant, presented a paper focused on these new concepts for wing components. He showed that properties of wing panels can be sequentially optimized along the length of the wing, to better match local design needs. Graded monolithic spars with significantly different properties in the upper and lower spar cap areas were also successfully developed.

Fuselage and wing concepts joined by laser-beam welding and FSW were described by Dr Frank Eberl from the Alcan R&D Center of Voreppe. He showed how these techniques can help to optimize properties of fuselage alloys. Ph. Lequeu and R. Maziarz from Airbus discussed applications to wing ribs. In both cases, third generation Al- Li alloys such as 2196, 2198, and 2050 were chosen for weight saving purposes; associated with welding, they were shown to offer efficient solutions at a reasonable cost.

Advanced conventional and Al-Li alloys were described in details in five papers. Paul Smith, R&D Manager at the Alcan Rolled Product division, Ravenswood, West Virginai, introduced the medium-gauge to heavy-gauge 7140-T7651 alloy developed in collaboration with Boeing. This alloys is aimed at providing better strength/ toughness property balance than the incumbent alloys.

Michael Philbrook introduced low- density 2050 Al-Li plate alloy for medium-gauge to heavy-gauge applications. Developed in conjunction with the Issoire plant, the plate is aimed at providing at least the same property balance as the 7050 baseline, but with the additional benefits of lower density, higher modulus, and better corrosion resistance. Finally, for similar types of applications, Dr Alex Cho presented the latest data on 2139, a silver- containing 2xxx alloy produced as plates up to six inches thick, and displaying outstanding fracture toughness with associated good strength levels.

Dr Herve Ribes, R&D sheet Products Manager at the Issoire plant, provided details of technology transfer, requalification, and optimization of 2098, another Al-Li alloy. Designed for fuselage components, it serves on the F-16 aircraft in several fracture critical components. Finally, an advanced derivative of this Alcan- developed alloy, registered as 2198, was presented by M. Knuewer from Airbus. This very high-strength and very high damage-tolerance fuselage alloy was shown to significantly outperform the 2524 baseline, and was adopted for A350 fuselage panels.