The chemical composition of UNS N19909（Incoloy 909）
Tech Center 2025-08-02 1
Incoloy 909 alloy is a nickel-iron alloy, whose outstanding properties are a constant low coefficient of thermal expansion, a constant elastic modulus and high strength. This alloy is strengthened through precipitation hardening heat treatment with the addition of niobium and titanium.
The combination of low expansion and high strength makes Incoloy 909 alloy particularly suitable for gas turbines. Low expansion enables tighter control of clearance and tolerance to achieve greater power output and fuel efficiency. High strength enhances the strength-to-weight ratio, making aircraft engines lighter in weight. For these reasons, Incoloy 909 alloy is used in the blades, casings, shafts and fairings of gas turbines.
The properties of Incoloy 909 alloy are also applicable to rocket engine nozzle chambers, military hardware, springs, steam turbine bolts, gauge blocks, instruments and glass sealing applications.
The density of this alloy is ρ=8.19g/cm³.
