Hastelloy C-276 is a nickel–chromium–molybdenum–tungsten (Ni-Cr-Mo-W) superalloy renowned for its exceptional resistance to pitting, crevice corrosion, stress-corrosion cracking, and chemical attack in both oxidizing and reducing environments.
It is considered one of the most corrosion-resistant nickel alloys available and is widely used in chemical processing, energy, pollution control, oil & gas, aerospace, and nuclear industries.
Strengthening & Metallurgical Behavior
Microstructure:
Single-phase FCC austenitic matrix
No gamma-prime precipitation
Excellent long-term microstructural stability
Strengthening Mechanisms:
Solid-solution strengthening (Mo + W)
Cold work (strain hardening)
Grain size control
Metallurgical Advantages:
Resistant to carbide precipitation
Excellent weldability without post-weld heat treatment
No embrittling phases during service
Corrosion & Environmental Resistance
Hastelloy C-276 exhibits outstanding resistance to:
✔ Pitting and crevice corrosion
✔ Chloride-induced stress corrosion cracking
✔ Wet chlorine gas
✔ Hypochlorite and chlorine dioxide
✔ Sulfuric, hydrochloric, and phosphoric acids
✔ Mixed and contaminated acid environments
It outperforms stainless steels, Monel alloys, and even Inconel 625 in many aggressive chemical environments.
Refining & Processing Properties
Melting & Refining:
Vacuum Induction Melting (VIM)
Vacuum Arc Remelting (VAR)
Fabrication:
Hot and cold working possible
Good machinability (relative to superalloys)
Excellent weldability (GTAW, GMAW, SMAW)
Post-weld solution annealing generally not required
Available Forms
Plates & sheets
Bars & rods
Pipes & tubes (seamless & welded)
Forgings
Wire
Fasteners
Key Characteristics
✔ Among the most corrosion-resistant alloys available
✔ Excellent fabricability and weldability
✔ High strength with good ductility
✔ Superior resistance to localized corrosion
✔ Stable in harsh mixed chemical environments
Applications
Chemical & Process Industry:
Reactors and pressure vessels
Heat exchangers
Acid handling systems
Evaporators
Pollution Control:
Flue gas desulfurization (FGD) units
Scrubbers and stacks
Waste incineration systems
Oil & Gas:
Sour gas service
Downhole components
Valves and fittings
Pulp & Paper:
Bleach plant equipment
Aerospace & Nuclear:
Critical corrosion-exposed components
Advantages
✔ Exceptional corrosion resistance in oxidizing & reducing media
✔ Outstanding resistance to pitting, crevice corrosion & SCC
✔ Excellent weldability
✔ High mechanical strength
✔ Long service life in extreme environments
Limitations
❌ High material and fabrication cost
❌ Lower thermal conductivity
❌ Heavier than titanium and aluminum
❌ Over-specification for mild environments
Why Choose Hastelloy C-276?
Choose Hastelloy C-276 when equipment is exposed to multiple aggressive chemicals, corrosion failure is unacceptable, welded structures require maximum corrosion resistance, and long-term reliability outweighs cost.
Engineering Insight:
Hastelloy C-276 is a benchmark nickel superalloy for extreme corrosion
environments, delivering unmatched reliability where conventional
materials fail.