Inconel 718
Inconel 718 – Precipitation-Hardened Nickel Superalloy for Jet Engines and High-Temperature Service
Inconel 718 is the most widely used nickel-based superalloy in the world, accounting for approximately 35% of all superalloy production. Its precipitation-hardened Ni-Cr-Fe microstructure maintains exceptional strength and creep resistance up to 700°C, making it the dominant material for jet engine discs, turbine blades, and high-temperature aerospace fasteners.
Key Properties
- Tensile Strength: 1275 MPa
- Continuous Service Temperature: Up to 700°C
- Hardness: 363 HB
- Density: 8.19 g/cm³
- Machinability: Difficult — requires specialized tooling
- Standards: AMS 5662 / ASTM B637
Common Applications
Jet engine turbine discs and blades, rocket motor components, gas turbine casings, cryogenic tankage, nuclear reactor hardware, and downhole oil and gas tooling subject to extreme temperature and pressure.
Material properties
| Material name | Inconel 718 |
|---|---|
| Type | Nickel Alloys |
| Standard code | AMS 5662 / ASTM B637 |
| Tensile strength (MPa) | 1275 |
| Yield strength (MPa) | 1034 |
| Fatigue strength (MPa) | 550 |
| Elongation (%) | 12 |
| Hardness (Brinell) | 363 |
| Density (g/cm³) | 8.19 |
| Electrical resistivity (µΩ·in) | 125 |
| Thermal conductivity (W/m·K) | 11.4 |
| Melting range (°C) | 1260–1336 |
| Weldability | Good |
| Formability | Fair |
| Shear modulus | 77.2 |
| Industry code | inconel_718 |