Hastelloy X

About Hastelloy X

Hastelloy X (also known as Haynes 230) is a nickel-chromium-iron-molybdenum superalloy renowned for its exceptional high-temperature strength, oxidation resistance, and fabricability. It is widely used in aerospace, gas turbines, and industrial heating applications where extreme heat and corrosive environments are present. 

Key Properties of Hastelloy X

  1. Chemical Composition (Typical wt.%)
Element Percentage Role
Nickel (Ni) ~47% (Balance) Base metal, provides corrosion resistance
Chromium (Cr) 20.5-23% Enhances oxidation resistance
Iron (Fe) 17-20% Stabilizes structure, lowers cost
Molybdenum (Mo) 8-10% Improves creep resistance
Cobalt (Co) 0.5-2.5% Enhances high-temperature strength
Tungsten (W) 0.2-1.0% Strengthens solid solution
Carbon (C) 0.05-0.15% Affects high-temperature stability

2. Key Characteristics

✔ Outstanding Oxidation Resistance – Performs well up to 1200°C (2200°F) due to a protective Cr₂O₃ layer. 

✔ Excellent Creep & Rupture Strength – Maintains structural integrity under prolonged stress at high temperatures. 

✔ Resistance to Reducing & Oxidizing Atmospheres – Suitable for both combustion and chemical environments. 

✔ Good Fabricability & Weldability – Can be welded (TIG, MIG), forged, and machined with proper techniques. 

Applications of Hastelloy X 

  1. Aerospace & Jet Engines

– Combustor liners, afterburners, turbine seals 

– Rocket engine components 

  1. Industrial Gas Turbines

– Burner cans, transition ducts, hot gas path components 

  1. Petrochemical & Chemical Processing

– Furnace components, heat exchangers, reformers 

Mechanical Properties (Room Temperature, Annealed Condition) 

Property Value
Tensile Strength 760 MPa (110 ksi)
Yield Strength (0.2% offset) 345 MPa (50 ksi)
Elongation (%) 35%
Hardness (Rockwell B) ~85 HRB

Comparison with Other Superalloys

Property Hastelloy X Inconel 617 Inconel 718 Haynes 230
Primary Strengthening Solid solution Solid solution + carbides γ” (Ni₃Nb) precipitates Solid solution
Max Temp (°C) 1200 1000 700 1200
Oxidation Resistance Excellent Very Good Moderate Excellent
Key Applications Combustors, turbines Nuclear reactors Aerospace, oil & gas Industrial heating

Advantages & Limitations 

 ✔ Advantages 

– Superior high-temperature oxidation resistance (up to 1200°C). 

– Excellent creep and rupture strength. 

– Good weldability and fabricability compared to other superalloys. 

 ✖ Limitations 

– Lower strength than precipitation-hardened alloys (e.g., Inconel 718). 

– Expensive due to high nickel and cobalt content. 

Conclusion 

Hastelloy X is a versatile, high-performance superalloy optimized for extreme heat and corrosive environments, making it indispensable in aerospace, power generation, and industrial heating applications. While it lacks the ultra-high strength of precipitation-hardened alloys, its thermal stability and oxidation resistance make it a top choice for demanding high-temperature applications. 

Related Products