What is Hastelloy C276 used for?
Alloy C-276 / UNS N10276 / W.Nr. 2.4819
Description
Alloy C-276 is a solid solution strengthened nickel-molybdenum-chromium alloy containing a small amount of tungsten. Alloy C-276 exhibits excellent corrosion resistance in a wide range of harsh environments and media. Like many other nickel alloys, it is ductile and easily formed and welded. This alloy is used in most industrial environments where corrosive chemical environments are present and other alloys have failed.
Industries and Applications
Alloy C-276 is frequently used in many industries including chemical and petrochemical processing, oil and gas, power generation, pharmaceuticals, pulp and paper production, and wastewater treatment. End-use applications include chimney linings, ducts, dampers, scrubbers, flue gas reheaters, heat exchangers, reaction vessels, evaporators, transfer ducts, and many other highly corrosive applications.
Corrosion Resistance
Alloy C-276 is one of the most prevalent corrosion resistant alloys available today. It can be used in a wide range of environments from moderately oxidizing to strongly reducing conditions. Alloy C-276 has excellent corrosion resistance to sulfuric, hydrochloric, formic, acetic, chlorides, solvents, wet chloride gases, hypochlorites, and chlorine solutions. Alloy C-276 has excellent resistance to phosphoric acid at all temperatures below the boiling point and concentrations below 65%. The limiting factor when dealing with strong oxidizing environments is the low chromium content, which means that hot concentrated nitric acid environments are undesirable.
Alloy C-276 has excellent resistance to pitting, stress corrosion cracking, and oxidizing atmospheres. Alloy C-276 also exhibits resistance to seawater corrosion in crevice conditions that can aggressively attack other commonly used materials.
Fabrication and Heat Treatment
Alloy C-276 can be formed using a variety of cold and hot working processes. Like other nickel alloys, C-276 alloy work hardens quickly but can be cold formed using aggressive methods such as deep drawing, press forming, and stamping. Hot forming should be done at temperatures between 1600°F and 2250°F (870°C and 1230°C), with heavier sections heated to a minimum of 2000°F before forming. It is recommended that the material be annealed after processing at temperatures between 2050°F and 2150°F, followed by a rapid quench in a protective atmosphere or in a stirred reduction quench tank. To obtain a reduction quench tank, add 2% (by volume) ethanol or propanol to water.
