Materials and processes have played a major role in enhancing the performance, improving the durability and maintainability, and reducing the cost of gas turbine engines over the past decades. These materials incldue: single crystal turbine airfoils, thermal barrier coatings, high temperature and high strength Ni shafts, damage tolerant and high creep strength powder metallurgy Ni alloy discs, hard-smooth compressor abradables and others. Over this same period, turbine inlet temperatures have gone fro mmid 2000 deg F to mid 3000 deg F and engines can go much longer between overhaul cycles. Military engines have thrust to weight ratio of greater than seven to one. Despite these advancements, materials development cost remains high and cycle time remains long, (5 to 10 years). Whereas, the engine development cycle time is at 30 months and heading toward 24 months in the next couple of years and toward 18 months in the 5 to 10 year range. Materials development cycle is helpelessly out of sync with the engine development cycle. One the other hand, materials engineers have developed or improved many processes that increase the yield, reduce process steps, reduce cycle time and improve the cost and quality of the parts/components.
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