René 41

René 41 is a nickel-based high temperature alloy developed by General Electric. It retains high strength in the 1200-1800 F temperature range. It is used in jet engine and missile components, and other applications that require high strength at extreme temperatures. René 41 is considered a nickel alloy based upon its chemical composition.

René 41 was used to create the outer shell of the Mercury space capsule, due to its ability to retain high strength at very high temperatures.