Excellent High-Temperature Performance of Hastelloy X
Hastelloy X is a nickel-based superalloy known for its outstanding high-temperature strength and oxidation resistance. It performs exceptionally well in extreme heat and stress environments, making it a preferred material in gas turbines, aircraft engines, and industrial furnaces. Hastelloy X also resists carburization and nitridation, maintaining structural integrity in severe thermal cycling conditions.
This article introduces the composition, properties, and applications of Hastelloy X to help engineers select optimal materials for elevated-temperature and corrosive environments.
What is Hastelloy X?
Hastelloy X (UNS N06002) is a wrought nickel-chromium-iron-molybdenum alloy designed for excellent oxidation resistance and high-temperature strength. It offers good formability and weldability, even after prolonged exposure to high temperatures. The alloy retains mechanical integrity in applications reaching up to 1200 °C (2200 °F).
Hastelloy X Equivalent Grades
| Standard / System | Equivalent Designation |
| UNS | N06002 |
| ASTM / ASME | ASTM B435, B619, B622, B626 |
| EN / DIN | 2.4665 |
| ISO | NiCr22Fe18Mo |
| JIS | NCF X |
Hastelloy X Chemical Composition
| Element | Content (%) |
| Nickel (Ni) | Balance |
| Chromium (Cr) | 20.5 – 23.0 |
| Iron (Fe) | 17.0 – 20.0 |
| Molybdenum (Mo) | 8.0 – 10.0 |
| Cobalt (Co) | 0.5 – 2.5 |
| Tungsten (W) | ≤ 1.0 |
| Carbon (C) | ≤ 0.10 |
| Manganese (Mn) | ≤ 1.0 |
| Silicon (Si) | ≤ 1.0 |
| Sulfur (S) | ≤ 0.030 |
Hastelloy X Mechanical Properties
| Property | Typical Value |
| Tensile Strength | 690 – 870 MPa |
| Yield Strength | ≥ 275 MPa |
| Elongation | ≥ 30% |
| Hardness (HBW) | ~200 |
Hastelloy X Physical Properties
| Property | Value |
| Density | 8.22 g/cm³ |
| Melting Point | 1260 – 1355 °C |
| Thermal Conductivity | ~11.4 W/m·K |
| Electrical Resistivity | ~1.29 µΩ·m |
| Modulus of Elasticity | ~210 GPa |
| Service Temperature Range | Up to 1200 °C |
Applications of Hastelloy X
- Gas Turbine Engines: Combustion chambers, tailpipes, and afterburners.
- Industrial Furnaces: Furnace liners, burners, and retorts.
- Aerospace Components: Jet engine exhaust systems and structural supports.
- Nuclear Reactors: High-temperature ducts and heat exchangers.
- Chemical Processing: Equipment exposed to oxidizing and carburizing atmospheres.
Advantages of Hastelloy X
- Exceptional oxidation resistance at temperatures up to 1200 °C.
- Strong thermal fatigue and creep resistance, ideal for cycling heat environments.
- Good fabricability and weldability, with resistance to grain-boundary corrosion.
- Excellent resistance to carburization and nitridation.
- Retains mechanical strength after long-term high-temperature service.
Limitations of Hastelloy X
- Not ideal for strong reducing environments like hydrochloric acid.
- Relatively high cost due to its complex alloying.
- Limited resistance to wet corrosion compared to C-series Hastelloys.
- Work hardens rapidly, requiring specialized machining practices.
Hastelloy X vs Other High-Temp Alloys
| Feature | Hastelloy X | Inconel 600 | Alloy 800H |
| Max Service Temp | ~1200 °C | ~1100 °C | ~1100 °C |
| Oxidation Resistance | Excellent | Very Good | Good |
| Thermal Fatigue | Excellent | Moderate | Good |
| Weldability | Excellent | Excellent | Good |
| Carburization Resistance | High | Moderate | Moderate |
Summary
Hastelloy X is a high-performance alloy engineered for extreme thermal and oxidizing conditions. Its combination of strength, oxidation resistance, and workability makes it a top choice in aerospace, furnace, and energy applications.
MT.BOLTS manufactures components and fasteners using Hastelloy X to meet the toughest temperature and stress challenges. Contact us to learn more or request a custom quote tailored to your application.
