Hastelloy X vs Inconel 718: 21% composition overlap. Significantly different materials serving different application areas.
Hastelloy X vs Inconel 718
Side-by-side chemical composition and mechanical property comparison.
Overview
Hastelloy X
2.4665
Nickel-chromium-iron-molybdenum solid-solution superalloy — exceptional combination of oxidation resistance, fabricability, and high-temperature strength. NOT age-hardenable (solid-solution only). Oxidation-resistant to 1200°C, good ductility after 16000h at 650-870°C. Outstanding formability and weldability for a superalloy. Used for gas turbine combustor cans, transition ducts, afterburners, furnace hardware, and petrochemical process equipment.
Inconel 718
2.4668
THE most widely used aerospace superalloy. Precipitation-hardened Ni-Cr-Fe alloy strengthened by gamma-prime and gamma-double-prime phases (Nb). Unique slow aging kinetics allow welding without cracking. UTS >1275 MPa aged. Used for gas turbine discs, jet engine components, rocket motors, cryogenic tanks, and oil/gas downhole tools. Service to 700°C.
| Hastelloy X | Inconel 718 | |
|---|---|---|
| Material Number | 2.4665 | 2.4668 |
| Category | Nickel Alloys | Nickel Alloys |
| Standard | ASTM B435 | ASTM B637 |
Chemical composition (wt%)
| Element | Hastelloy X | Inconel 718 | Overlap |
|---|---|---|---|
| C | 0.05–0.15% | 0–0.08% | Partial |
| Si | 0–1% | 0–0.35% | OK |
| Mn | 0–1% | 0–0.35% | OK |
| Cr | 20.5–23% | 17–21% | Partial |
Mechanical properties
| Property | Hastelloy X | Inconel 718 | Unit |
|---|---|---|---|
| tensile_strength | 690–760 | ≥ 1275 | MPa |
| yield_strength | 275–345 | ≥ 1034 | MPa |
| elongation | 35–45 | ≥ 12 | % |
Compatibility Assessment
Hastelloy X and Inconel 718 have significantly different compositions (21% overlap). These materials are not interchangeable and serve different application areas.
Automated assessment based on composition analysis
Frequently Asked Questions
Is Hastelloy X the same as Inconel 718?
Hastelloy X and Inconel 718 have a 21% composition overlap. They are generally not directly interchangeable.
Can I replace Hastelloy X with Inconel 718?
Generally not recommended. The compositions differ significantly (21% overlap). These materials have different alloying concepts and are intended for different applications.
What is the difference between Hastelloy X and Inconel 718?
The main differences are in the following elements: C, Cr, Mo, Co. Hastelloy X is a Nickel Alloys grade, while Inconel 718 is a Nickel Alloys grade.
Related Comparisons
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