HASTELLOY X is a wrought nickel base alloy with excellent high temperature strength and oxidation resistance. All of the product forms are excellent in terms of forming and welding. Although HASTELLOY X is primarily noted for heat and oxidation resistance it also has good resistance to chloride stress-corrosion cracking and has good resistance to carburization, excellent resistance to reducing or carburizing atmospheres. Alloy X is one of the most widely used nickel base superalloys for gas turbine engine components.

AMS 5754 has no yield or tensile strength requirements, but it does require a hardness maximum and stress rupture minimums. Strong and Oxidation Resistant to 2200 Deg. F (1200 Deg. C) - HASTELLOY X is a solid solution strengthened grade has good strength and oxidation resistance up to 2200 Deg. F (1200 Deg. C).

Characteristics

RESISTANCE TO OXIDATION
The outstanding oxidation resistance of HASTELLOY X is illustrated below. Tests were conducted by exposing samples to dry air at 2000 Deg. F. and to dry air pressurized to 300 psi at 1750 Deg. F. Two criteria for evaluating oxidation resistance are weight change and depth of corrosion penetration. HASTELLOY X excels in both respects due to the formation of a protective, tenacious oxide film.

RESISTANCE TO CARBURIZATION AND NITRIDING
HASTELLOY X also resists carburization and nitriding, two common conditions which often lead to early failure in high-temperature alloys. After 100 hours in petroleum coke, four other materials were completely penetrated by carburization; whereas, Alloy X specimens showed no carburization at all. Of ten materials evaluated in an atmosphere of hydrogen, nitrogen and ammonia at 1100 Deg. F. and 25,00 psi for 64 days, Alloy X had a nitride case less than one-fourth as thick as the closest competitive material without intergranular attack.

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