Inconel 718

Material Data Sheet

Inconel 718 is a vacuum melted (double or triple melted for cleanliness) precipitation-hardening nickel alloy.

It maintains its high strength, oxidation, and corrosion resistance while maintaining its superior ductility under extreme environments. Inconel 718 is used in many industries for critical applications including aerospace, defense and petrochemical. Inconel 718 is characterized by having superb tensile, fatigue, creep and rupture strength at temperatures up to 1290 °F (980 °C). This makes it ideal for many high-temperature applications such as gas turbine, instrumentation, and power/process industry parts. It also has excellent utility for cryogenic applications. Parts built from Inconel 718 can be easily post-hardened through precipitation-hardening heat treatments. In both traditional and age-hardened states, the parts can be machined, spark eroded, welded, micro shot-peened, polished and coated if required.

The 4 main Inconel 718 bar stocking positions taken by Alloys International, Inc. are in accordance with AMS 5662 solution treated, AMS 5663 and 5664 solution treated and aged and NACE MR-01-75. For other forms please see the chart below.

NACE MR-01-75, produced in accordance with the API (American Petroleum Institute), is in a separate category from the AMS material, with adjusted chemistry that allows for the material to have a different range of characteristics. It also employs an adjusted annealing and aging temperature, which produces a product with lower mechanicals, larger grain and increased toughness. This is generally preferred for many oil, offshore, and OEM applications.

Chemical Composition
Element Content (%)
Iron, Fe Balance
Nickel, Ni 50.0 – 55.0
Chromium, Cr 17.0 – 21.0
Niobium, Nb 4.7 – 5.5
Molybdenum, Mo 2.8 – 3.3
Cobalt, Co ≤ 1.0
Titanium, Ti 0.65 – 1.15
Manganese, Mg ≤ 0.35
Phosphorus, P ≤ 0.35
Copper, Cu ≤ 0.3
Aluminum, Al 0.2 – 0.8
Carbon, C ≤ 0.08
Sulfur, S ≤ 0.015
Physical Properties
Properties Metric Imperial
Density 8.192 g/cm3 0.296 lb/in3
Melting Range 1370-1430°C 2500-2600°F
Specific Gravity 8.19 8.19
Mechanical Properties
Properties Metric Imperial
Tensile Strength, Ultimate 1375 MPa 199000 psi
Tensile Strength, Yield 1100 MPa 160000 psi
Elongation at Break 25% 25%
Applications
  • Cryogenic storage tanks

  • Downhole shafting

  • Gas turbine components

  • High strength bolting

  • Jet engines

  • Pump parts

  • Pump shafts

  • Rocket motors

  • Thrust reversers

  • Nuclear fuel element spacers

Key Words:IN718, inco 718, inco-718, inconel-718, INCONEL 718, AFNOR NC 19 Fe Nb, UNS N07718; ASTM B637, B670; ASME Boiler Code Sections I, III; AMS 5589, AMS 5590, AMS 5596, AMS 5597, AMS 5662, AMS 5663, AMS 5664, AMS 5832, Werkstoff Nr. 2.4668; WL Nr. 2.4668; MIL-N-24469; NACE MR-01-75; AECMA Pr EN 2404, 2405, 2407, 2408, 2952, 2961, 3219