A precipitation-hardenable nickel-chromium grade, Alloy 718, often referred to as Inconel® 718, is a high strength superalloy used at temperatures up to 648°C.

With the addition of significant amounts of niobium and molybdenum along with aluminium and titanium, Alloy 718 has extremely high strength, excellent creep-stress rupture strength and good corrosion resistance.

  • UNS Number: N07718
  • Werkstoff Number: 2.4668
  • ASTM: B637, B670
  • AMS: 5596, 5662, 5663, 5832

Product availability

Round Bar
Welding Wire

Chemical analysis



  • Gas turbine engine parts
  • Liquid fuel rocket motor components
  • Springs, fasteners
  • Cryogenic tanks
  • Pumps and valves
  • Tooling

About Alloy 718

Alloy 718, often referred to as Inconel® 718, is precipitation hardened to give maximum strength and high creep-stress rupture strength. The alloy can be supplied in the annealed condition to enhance machinability followed by subsequent appropriate heat treatments. Capability tests are completed on test samples which have had the precipitation hardening process completed.

Alloy 718/Inconel® 718, demonstrates outstanding weldability including resistance to post-weld cracking.

The major applications are components for gas turbines, aircraft engines, fasteners and other high strength applications. Its available in round bar, wire and sheet and plate.

For more information on Nickel Alloy 718, or to get a quote contact us or fill in our online quote form.

  • Density: 8.193 g/cm³
  • Melting range: 1321-1393°C

Mechanical & Physical Properties

Mechanical & Physical Properties-196°C21°C93°C204°C316°C538°C649°C760°C
Coefficient of Thermal Expansion µm/m⁰C10.62-13.113.513.914.615.116
Thermal Conductivity /kcal/(hr.m.°C)-9.510.712.213.816.818.319.8
Modulus of Elasticity / x105 MPa-21.931.861.791.721.651.52

Typical Room Temperature Properties, 982°C

135Ultimate tensile strength, ksi
700.2% yield strength, ksi
45Elongation, %
100Hardness, Rockwell B

Average Tensile Properties, ½” Bar Annealed 982°C

Temperature, °C21°C204°C427°C538°C649°C760°C
Ultimate Tensile Strength, ksi210198191185168111
0.2% Yield Strength, ksi175163156155149110
Elongation, %222019181927
Hardness, Rockwell C42-44--40-4140-4133-34

Typical Stress Rupture, Bar, Annealed 982°C

100 Hours, ksi1701107544
1,000 Hours, ksi130855525
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