Inconel 718 is a high-strength, corrosion-resistant nickel-chromium alloy known for its outstanding mechanical properties across a wide temperature range, especially in aerospace, nuclear, and high-temperature industrial applications.
🔧 Key Mechanical and Physical Properties of Inconel 718
| Property | Value / Range | Notes |
|---|---|---|
| Density | 8.19 g/cm³ (0.296 lb/in³) | High density due to Ni and alloying elements |
| Melting Point | 1,260 – 1,335 °C (2,300 – 2,435 °F) | Suitable for high-temperature applications |
| Tensile Strength | 1,200 MPa – 1,500 MPa | Depends on heat treatment (solution + aged) |
| Yield Strength (0.2% offset) | 1,000 MPa – 1,250 MPa | High resistance to deformation |
| Elongation at Break | 10% – 20% | Good ductility for a high-strength alloy |
| Hardness | ~331 HB (solution treated) ~444 HB (aged) |
Increases significantly after age hardening |
| Modulus of Elasticity | ~200 GPa (29 x 10⁶ psi) | Comparable to other Ni-based alloys |
| Thermal Conductivity | 11.4 W/m·K @ 21 °C | Relatively low; affects heat dissipation during machining |
| Coefficient of Expansion | 13.0 µm/m·K (20–100 °C) | Should be considered in high-temperature assemblies |
| Specific Heat Capacity | 435 J/kg·K | Moderate heat capacity |
| Corrosion Resistance | Excellent in many acidic and high-temperature environments | Resistant to oxidation, pitting, and stress corrosion cracking |
⚙️ Key Characteristics of Inconel 718
Excellent creep and rupture strength at temperatures up to 700 °C (1,300 °F)
Age hardenable, allowing complex parts to be heat-treated after fabrication
Resistant to chloride-ion stress corrosion cracking
Maintains mechanical properties at cryogenic temperatures
