HAYNES® 718 alloy (UNS N07718) is an age-hardenable nickel-iron-niobium( chromium)-niobium (columbium)-molybdenum-titanium-aluminum alloy designed to combine excellent strength with good fabrication characteristics in the annealed condition. While limited to applications below 1200°F (650°C), it is significantly stronger at these lower temperatures than materials such as Waspaloy alloy, R-41 alloy, or X-750 alloy. It is also much easier to weld than these alloys, and is less susceptible to the strain age cracking problems common for gamma prime strengthened materials. At temperatures greater than 1200°F (650°C), 718 alloy is being replaced by HAYNES® 282® alloy due to the superior strength of 282® alloy at those temperatures as well as its excellent fabricability.
HAYNES® 718 alloy is normally only used for component applications up to 1200°F (650°C); however, its oxidation resistance is comparable to that for other gamma-prime-strengthened superalloys.