Inconel 718 (UNS N07718): Precipitation-Hardening Aerospace Superalloy
AMS 5662 · Published: 2026-06-03 · Updated: July 2026
Inconel 718 is the most widely used nickel-based superalloy — accounting for approximately 35% of all superalloy production by weight. It achieves exceptional strength through precipitation of gamma-double-prime (Ni₃Nb) phases during aging,...
Inconel 718 is the most widely used nickel-based superalloy — accounting for approximately 35% of all superalloy production by weight. It achieves exceptional strength through precipitation of gamma-double-prime (Ni₃Nb) phases during aging, maintaining useful strength to 650°C. It is the dominant material for jet engine rotating components (discs, shafts, blades) and high-temperature fasteners.
Quick Facts
| Category | Nickel Alloy |
| Standard | AMS 5662 |
| Density | 8.19 g/cm³ |
| Yield Strength | 1,034 MPa |
| Tensile Strength | 1,275 MPa |
Global Equivalents & Cross-Reference
| Alternative Standard / Grade | Action |
|---|---|
| EN 2.4668 | Compare |
| NiCr19NbMo | Compare |
| JIS NCF718 | Compare |
| GB GH4169 | Compare |
Related Materials
🧮 Material Weight Calculator
Calculate the weight based on this material's density: 8.19 g/cm³
Frequently Asked Questions
What makes 718 the most produced superalloy?
718 combines (1) exceptional strength at temperature, (2) good weldability compared to other superalloys, (3) relatively slow aging response allowing thick-section heat treatment without cracking, and (4) widespread availability due to decades of aerospace qualification. No other superalloy matches this combination.
References & International Standards
- ASTM International. Standard Specifications for Steel & Metal Alloys. astm.org
- International Organization for Standardization (ISO). Metallic Materials — Cross-Reference Database. iso.org
- American Iron and Steel Institute (AISI). Steel Grade Designations & Equivalents. steel.org
- European Committee for Standardization (CEN). EN Steel Standards & Numbering System. cencenelec.eu