When selecting nickel-based alloys for extreme corrosion, high temperature, or high-stress environments, Inconel 718 and Hastelloy C276 are frequently compared. Although both are premium superalloys, their chemical composition reflects fundamentally different design priorities, which directly impacts corrosion resistance, mechanical strength, service temperature, and cost.
What is Inconel 718?
Inconel 718 (UNS N07718) is a high-strength, nickel-chromium superalloy known for exceptional resistance to corrosion and high temperatures (up to 1300°F/704°C), maintaining strength at extreme heat, and excellent weldability. It's age-hardenable, meaning it gets stronger with heat treatment, making it ideal for demanding aerospace (jet engines, rockets), oil & gas (downhole tools), and industrial parts requiring high performance in corrosive or high-heat environments.
What is Hastelloy C276?
Hastelloy C-276 (UNS N10276) is a highly versatile nickel-chromium-molybdenum superalloy known for exceptional corrosion resistance in severe chemical environments, particularly against pitting, crevice corrosion, and stress-corrosion cracking in chlorides, thanks to its low carbon/silicon content and high molybdenum/chromium/tungsten levels, making it ideal for chemical processing, oil & gas, and marine industries in applications like reactors, heat exchangers, and scrubbers.
Inconel 718 alloy specifications
Inconel 718 vs. Hastelloy C276 ：Material
| Alloy | Primary Design Goal |
|---|---|
| Inconel 718 | High strength, fatigue resistance, and creep resistance at elevated temperatures |
| Hastelloy C276 | Maximum resistance to aggressive corrosion (acids, chlorides, pitting, crevice attack) |
Inconel 718 vs. Hastelloy C276 ： Composition
| Element | Inconel 718 (UNS N07718) | Hastelloy C276 (UNS N10276) |
|---|---|---|
| Nickel (Ni) | 50.0 – 55.0 | Balance (~57%) |
| Chromium (Cr) | 17.0 – 21.0 | 14.5 – 16.5 |
| Molybdenum (Mo) | 2.8 – 3.3 | 15.0 – 17.0 |
| Iron (Fe) | Balance | 4.0 – 7.0 |
| Niobium (Nb + Ta) | 4.75 – 5.5 | - |
| Cobalt (Co) | ≤1.0 | ≤2.5 |
| Tungsten (W) | - | 3.0 – 4.5 |
| Carbon (C) | ≤0.08 | ≤0.01 |
| Silicon (Si) | ≤0.35 | ≤0.08 |
Inconel 718 vs. Hastelloy C276 ： Application
| Application Environment | Recommended Alloy |
|---|---|
| Aerospace engine disks | Inconel 718 |
| Oil & gas downhole tools | Inconel 718 |
| HCl reactors & scrubbers | Hastelloy C276 |
| Flue gas desulfurization | Hastelloy C276 |
| High-load fasteners | Inconel 718 |
| Heat exchangers (acidic) | Hastelloy C276 |
Inconel 718 vs. Hastelloy C276 ： Mechanical Properties Table (Room Temperature, Typical Values)
| Property | Inconel 718 (UNS N07718) | Hastelloy C276 (UNS N10276) |
|---|---|---|
| Tensile Strength | 1,240 – 1,450 MPa | 690 – 790 MPa |
| Yield Strength (0.2% offset) | 1,030 – 1,200 MPa | 280 – 355 MPa |
| Elongation | 12 – 20 % | 40 – 60 % |
| Reduction of Area | 20 – 30 % | ≥ 55 % |
| Hardness | 36 – 45 HRC (aged) | 20 – 28 HRC |
| Elastic Modulus | ~200 GPa | ~205 GPa |
| Density | 8.19 g/cm³ | 8.89 g/cm³ |
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Inconel 718 vs. Hastelloy C276 ：High-Temperature Mechanical Performance
| Performance Aspect | Inconel 718 | Hastelloy C276 |
|---|---|---|
| Maximum strength retention | Up to ~650 °C | Up to ~400 °C |
| Creep resistance | Excellent | Moderate |
| Fatigue resistance | Excellent | Good |
| Stress rupture strength | Very high | Limited |
Inconel 718 suppliers
At GNEE, Inconel 718 is available in various forms to meet diverse industrial needs:
Plates and Sheets (cold rolled and hot rolled)
Bars and Rods (round, square, hexagonal)
Tubes (seamless and welded)
Wires and Strips (for springs, fasteners, electrical applications)
Forgings and Custom Parts (according to drawings or specifications)
Specifications: UNS NO7718, WNR 2.4668, AFNOR NC19FeNb, JIS NCF 718, GOST ХН75МБТЮ, EURONORM NiCr22Mo9Nb, OR ЭИ602, BS NA 21.
Temperature Range: -423°F to 1300°F.
Testing and Documentation: Mill Test Certificates, EN 10204 3.1, Chemical Reports, Mechanical Reports, Destructive Testing Reports, Non-Destructive Testing Reports, PMI Test Reports, Visual Inspection Reports, Third-Party Inspection Reports, NABL Certified Laboratory Reports.
Packaging: Wooden crates, bubble wrap, steel strapping, or packaged according to customer requirements.
