UNS: N07718
W.Nr: 2.4668
Printable PDF: Inconel® 718 Alloy
Inconel® 718 is an age-hardenable Nickel-Chromium-Columbium (Niobium)-Molybdenum alloy with high strength, corrosion- resistance, and good fabrication characteristics. Inconel® 718 has high tensile, yield, and creep-rupture properties at high temperatures and can operate at cryogenic temperatures up to 1200°F (650°C).
Applications include springs, valves, and aircraft and land-based turbine engines.
Industries supplied include: Oil & Gas Extraction, Nuclear, Aerospace, Defense and Automotive.
Nominal Composition
| Ni: | 50 – 55 |
| Cr: | 17 – 21 |
| Cb (Nb): | 4.75 – 5.5 |
| Mo: | 2.8 – 3.3 |
| Ti: | 0.65 – 1.15 |
| Fe: | BAL |
| Co: | 1.0 max |
| Al: | 0.2 – 0.8 |
| Mn: | 0.35 max |
| Si: | 0.35 max |
| Cu: | 0.3 max |
Physical Properties
At 70°F (At 20°C)
Density
0.296 lb./in3 / (8.19 g/cm3)
Modulus of Elasticity (E)
29 x 103 ksi / (200 GPa)
Modulus of Rigidity (G)
11.6 x 103 ksi / (80 GPa)
Coefficient of Expansion
7.7 microinches/in.-°F (70-600°F) / (13.9 μm/m-°C) (20-300°C)
Electrical Resistivity
47.5 μ ohm.in / (121 μ ohm.cm)
Thermal Conductivity
79 Btu-in./ft.2hr.-°F / (11.4 W/m-K)
Applicable Specifications
Wire & Bar – AMS 5662, AMS 5663, AMS 5664, AMS 5832, AMS 5962,
ASME SB-637, ASTM B637, AWS A5.14, NACE MR0175 (ISO 15156-3)
Typical Mechanical Properties
*Condition
Annealed (Min)
Heat Treatment
1800°F (980°C)
Tensile Strength
115 – 145 ksi (790 – 1000 MPa)
Suggested Operating Conditions
-330°F to 1200°F (-200°C to 650°C)
*Condition
Spring Temper (Min)
Heat Treatment
Tensile Strength
190 – 220 ksi (1310 – 1515 MPa)
Suggested Operating Conditions
-330°F to 1200°F (-200°C to 650°C)
*Condition
Spring Temper + Aged (Min)
Heat Treatment
After spring coiling.
Age: 1325oF (720oC) for 8 hours, furnace cool to 1150°F and hold for a total aging time of 18 hours.
Tensile Strength
220 ksi (1515 MPa)
Suggested Operating Conditions
-330°F to 1200°F (-200°C to 650°C)
Inconel® is a registered trademark of the Special Metals Corporation group of companies.
