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Glass laminate aluminium reinforced epoxy (GLARE) is a fiber metal laminate (FML) composed of several very thin layers of metal (usually aluminium) interspersed with layers of glass-fiber "pre-preg", bonded together with a matrix such as epoxy. The uni-directional pre-preg layers may be aligned in different directions to suit the predicted stress conditions. Although GLARE is a composite material,〔http://users.ox.ac.uk/~smit0008/Publications_files/ORI-Aviation-Materials-2009.pdf〕 its material properties and fabrication are very similar to bulk aluminium metal sheets. It has far less in common with composite structures when it comes to design, manufacture, inspection or maintenance. GLARE parts are constructed and repaired using mostly conventional metal material techniques. Its major advantages over conventional aluminium are: * Better "damage tolerance" behavior (especially impact and metal fatigue, as the elastic strain is larger than other metal material it can consume more impact energy. It is dented easier but has a higher penetration resistance ) * Better corrosion resistance * Better fire resistance * Lower specific weight Furthermore, it is possible to "tailor" the material during design and manufacture such that the number, type and alignment of layers can suit the local stresses and shapes throughout the aircraft. This allows the production of double-curved sections, complex integrated panels or very large sheets, for example. While a simple manufactured sheet of GLARE will be more expensive than an equivalent sheet of aluminium, considerable production savings can be made using the aforementioned optimization. A structure properly designed for GLARE will be significantly lighter and less complex than an equivalent metal structure, and will require less inspection and maintenance and enjoy a much longer lifetime-till failure, making it a cheaper, lighter and safer option overall. == History == GLARE is a relatively successful FML, patented by Akzo Nobel in 1987, which has entered commercial application in the Airbus A380. The several patents mention among others as inventors Vogelesang, Schijve, Roebroeks and Marissen,〔Garesche, C. E., Roebroeks, G. H. J. J., Greidanus, V., Gunnink, J. W., Oost, R. C., & Greidanus, B. (1994). Laminated panel for aircraft fuselage - comprises metal layers with splices in staggered relation in adjacent layers and fibre-reinforced adhesive layers between the metal layers.〕〔 Schijve, J., Vogelesang, L., & Marissen, R. (1982). Laminate aluminium contg. metal sheets and aramid fibre sheets - bonded together by thermosetting adhesives, used in spacecraft and aircraft.〕 then professors and researchers at the Faculty of Aerospace Engineering, Delft University of Technology, where much of the on FML was done in the 1970s and 1980s. The fruition of FML development marks an important step in the long history of research starting in 1945 at Fokker, where earlier bonding experience at de Havilland inspired investigation into the improved properties of bonded aluminium laminates compared to monolithic aluminium. Later, NASA got interested in reinforcing metal parts with composite materials as part of the Space Shuttle program led to the introduction of fibers to the bond layers, and the concept of FMLs was born. Further research and co-operation of Fokker with Delft University, the Dutch Aerospace Laboratory NLR, 3M, Alcoa and various other companies and institutions led to the first FML, the Aramid fiber based ARALL. This proved to have some cost, manufacturing and application problems (while it had a very high tensile strength; compression, off-axis loading and cyclic loading proved problematic), which lead to an improved version with glass-fiber instead of aramid fibers. Over the course of the development of the material, which took more than 30 years from start to the major application on the Airbus A380, many other production and development partners have been involved, including Boeing, McDonnell Douglas, Bombardier, and the US Air Force.〔Berends, H., van Burg, E., & van Raaij, E. M. (2011). (Contacts and contracts: Cross-level network dynamics in the development of an aircraft material. ) Organization Science, 22(4), 940–960.〕 Over the course of time, companies withdrew from this involvement, sometimes to come back after a couple of years, like Alcoa who withdrew in 1995 to come back in 2004 and withdrew once again in 2010. These strategic decisions show the dynamic nature of innovation processes.〔Van Burg, E., Berends, H., & van Raaij, E. M. (2014). (Framing and Interorganizational Knowledge Transfer: A Process Study of Collaborative Innovation in the Aircraft Industry. ) Journal of Management Studies, 51(3), 349–378.〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「GLARE」の詳細全文を読む スポンサード リンク
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