AMS 5663 is a designation of Nickel Inconel 718, itself a nickel-chromium alloy with high strength, corrosion and oxidation resistance, and excellent tensile and impact strength at cryogenic temperatures.
Full chemical composition is 52.5Ni – 19Cr – 3.0Mo – 5.1Cb (Nb) – 0.90Ti – 0.50Al – 18Fe.
This designation is made by solution annealing at 1775°F (968°C) followed by rapid cooling, usually in water, and precipitation hardening at 1325°F (718°C) for 8 hours and furnace cool to 1150°F (620°C). Hold at 1150°F (620°C) for a total aging time of 18 hours.
It is available as bars, forgings, and rings, and thus it is a perfect option for parts that require resistance to creep and stress-rupture of up to 1300°F (705°C), and oxidation resistance of up to 1800°F (982°C).
Efficiency when welding is about 100% with the gas tungsten-arc process and using the proprietary Nickel Filler Metal 718. Nickel Inconel 718 AMS 5663 can be age-hardened directly, without stress relief.