FUTURE MATERIALS AND PROCESS FOR AIRCRAFT APPLICATIONS

Development of alloys and materials have played a significant role in the development of aircraft. The development of duraluminium which has still a lion's:;hare of the percentage of the airframe weight was dev eloped a few years after Wright brothers first flight of the powered a ircraft in 1903. With increased demands for higher strength, structura l integrity with minimum weight catalysed the development of a number of high strength aluminium alloys, special steels, Mg. alloys, a varie ty of composite materials. Engine temperatures have steadily increased from 150 degrees C in the early water cooled engines to over 1100 deg rees C in today's Turbojet engines and may So well beyond 2000 degrees C in the advanced jet engines planned for the future aircraft. The fu ture supersonic/hypersonic aircraft would pose challenge for even the airframe materials as the skill temperature at such high speeds will h e of the order of 250 degrees-300 degrees C. New requirements such as stealth characteristics, smart/intelligence characteristics are being sought now in addition to the traditional properties, such as high str ength to weight ratio, high stiffness, higher fatigue strength, fractu re toughness, lower rate of crack propagation and environmental tolera nce, etc. Therefore demand for the development of newer, smarter and i ntelligent materials is assuming greater significance. These are met b y development of newer alloys and materials, engineered materials such as reinforced plastic composites and new process technologies, This p aper tracts development of materials and applications front early airc raft to modern jumbojet and projecting to the future both for aircraft and engine materials.