Alloy C276
Alloy C-276 is a nickel-molybdenum-chromium alloy that is strengthened through solid solution hardening and contains a small amount of tungsten. It is highly resistant to corrosion across a wide range of aggressive environments. Like many other nickel-based alloys, Alloy C-276 offers excellent ductility and can be easily fabricated and welded. Due to its exceptional performance in extreme chemical conditions, it is widely used in industries where other materials fail.
Most Common Industries For Alloy C-276
Alloy C-276 plays a crucial role in industries such as chemical and petrochemical processing, oil and gas, power generation, pharmaceuticals, pulp and paper production, and wastewater treatment. It is commonly used for components exposed to highly corrosive environments, including stack liners, ducts, dampers, scrubbers, heat exchangers, reaction vessels, evaporators, and transfer piping.
Superior Resistance to Corrosion
Regarded as one of the most corrosion-resistant alloys available, Alloy C-276 performs well in conditions ranging from mildly oxidizing to strongly reducing. It has outstanding resistance to sulfuric acid, hydrochloric acid, formic acid, acetic acid, chlorides, solvents, wet chloride gas, hypochlorite, and chlorine solutions. It is highly effective in environments with phosphoric acid at concentrations below 65% and temperatures below boiling. However, due to its lower chromium content, it is not recommended for use in highly concentrated, hot nitric acid environments.
With superior resistance to pitting, stress corrosion cracking, and oxidation, Alloy C-276 is also highly durable in seawater applications, especially in crevice conditions where other materials may fail.
Fabrication & Heat Treatment
Alloy C-276 can be processed using both cold and hot working techniques. Although it work-hardens rapidly, it is still suitable for cold forming methods such as deep drawing, press forming, and punching. For hot forming, the recommended temperature range is between 1600°F and 2250°F (870°C to 1230°C), with thicker sections requiring at least 2000°F for optimal forming. Post-processing annealing is advised, ideally between 2050°F and 2150°F, followed by rapid quenching in a controlled atmosphere or a reducing quench bath. Adding 2% ethyl or propyl alcohol to water can create an effective reducing quench bath.
Equivalent Trade Names
- INCONEL® alloy C-276
- Hastelloy® C-276 alloy
INCONEL® is a trademark of Special Metals Corporation. HASTELLOY® is a trademark of Haynes International Inc.