Hastelloy C-276 (UNS N10276) is a nickel-molybdenum-chromium superalloy known for its exceptional resistance to strong oxidizing and reducing environments. It is widely used in chemical processing, environmental protection, marine engineering, and high-performance industrial equipment. As a trusted supplier of alloy materials, SASA ALLOY provides this brief guide to the key processing and fabrication techniques for Hastelloy C-276.
1.Melting and Hot Working
Hastelloy C-276 is typically produced using Vacuum Induction Melting (VIM) or Electroslag Remelting (ESR) to ensure high purity and homogeneous microstructure.
The hot forging temperature range is between 1175°C and 900°C. Forging should not be conducted below 900°C to prevent cracking or work hardening.
Standard heat treatment:
Solution Annealing at 1121°C followed by rapid water quenching
This treatment improves corrosion resistance and restores ductility.
2.Weldability and Recommendations
Hastelloy C-276 exhibits excellent weldability and is compatible with a wide range of welding processes including:
• TIG (GTAW)
• MIG (GMAW)
• Manual Shielded Metal Arc Welding (SMAW)
• Plasma Arc Welding (PAW)
Recommended filler metals:
• ERNiCrMo-4 for TIG/MIG
• ENiCrMo-4 for SMAW
Welding Tips:
• No preheating required; surface must be free of oil and contaminants
• Post-weld heat treatment is generally not recommended
• Interpass temperature should be kept below 150°C
• Use dedicated tools to avoid carbon steel contamination
3.Machining Characteristics
As a nickel-based alloy with a high work-hardening rate, Hastelloy C-276 is relatively difficult to machine. The following practices are recommended:
| Aspect | Recommendation |
| Cutting tools | Cemented carbide or premium HSS tools |
| Cutting speed | Low (20–30 m/min) |
| Feed rate | Moderate to low, to avoid excessive hardening |
| Cooling | High-performance coolant or emulsion fluid |
4.Surface Treatment and Cleanliness
After hot forming or welding, surface oxide scales should be removed by acid pickling or sandblasting. A mixed solution of nitric and hydrofluoric acid may be used under strict control to avoid damaging the base material.
Important: Tools and workbenches should be separated from carbon steel environments to prevent surface contamination.
5.Common Application Areas
Due to its superior resistance to aggressive media, Hastelloy C-276 is widely used in:
• Chemical reactors and storage tanks
• Heat exchangers and evaporators
• FGD (Flue Gas Desulfurization) systems
• Seawater and brine applications
• Pharmaceutical and nuclear process systems
Post time: May-19-2025