Hastelloy Alloy C-276 Introduction to Characteristics and Execution Standards

Hastelloy Alloy C-276  Introduction to Characteristics and Execution Standards

Common Trade Names include: Hastelloy C276, Alloy C-276, Nickel C-276; Nickelvac HC-276, Inconel C-276, Nicrofer 5716.

What is Hastelloy C-276 Alloy?

Alloy C-276 (UNS N10276, W.Nr. 2.4819) is known for its corrosion resistance in a wide range of aggressive media. The high molybdenum content imparts resistance to localized corrosion such as pitting.

The low carbon minimizes carbide precipitation during welding to maintain resistance to intergranular attack in heat-affected zones of welded joints. It's used in chemical processing, pollution control, pulp and paper production, industrial and municipal waste treatment and the recovery of “sour” natural gas.

Applications in air pollution control include stack liners, ducts, dampers, scrubbers, stack-gas re-heaters, fans and fan housings. In chemical processing, the alloy is used for components including heat exchangers, reaction vessels, evaporators and transfer piping.

What are the Benefits?

Hastelloy C-276 Alloy has excellent resistance to a wide variety of chemical process environments, including :

Strong oxidizers (such as ferric and cupric chlorides);

Hot contaminated media (organic and inorganic);

Chlorine;

Formic and acetic acids;

Acetic anhydride;

Seawater and brine solutions;

Moreover, it's used in flue gas desulfurization systems because of its excellent resistance to sulfur compounds and chloride ions encountered in most scrubbers. The product, such as Hastelloy C-276 pipe, also has excellent resistance to pitting and to stress-corrosion cracking. It's one of the few materials that withstands the corrosive effects of wet chlorine gas, hypochlorite, and chlorine dioxide.

Available Hastelloy Product Forms:

Pipe, tube, fitting, flange, sheet, strip, plate, round bar, flat bar, fastener, forging stock, hexagon and wire

Specifications:Hastelloy alloy C-276 is designated as UNS N10276 and Werkstoff Nr. 2.4819. It is listed in NACE MR0175 for oil and gas service. 

Rod, Bar, Wire and Forging Stock: ASTM B 462 (Rod, Bar and Forging Stock), ASTM B 564 & ASME SB 564 (Forgings), ASTM B 574 & ASME SB 574 (Rod, Bar and Wire), ISO 9723 (Rod and Bar), ISO 9724 (Wire), ISO 9725 (Forgings), DIN 17752, DIN 17753, DIN 17754, VdTÜV 400/12.98

Plate, Sheet and Strip: ASTM B 575; ASTM B 906; ASME SB 575; ASME SB 906, ISO 6208, DIN 17750, VdTÜV 400/12.98.

Pipe and Tube: - ASTM B 622; ASTM B 829 & ASME SB 622 ASME SB 829 (Seamless Tube), ASTM B 626; ASTM B 751 & ASME SB 626; ASME SB 751 (Welded Tube), ASTM B 619; ASTM B 775 & ASME SB 619; ASME SB 775 (Welded Pipe), ISO 6207 (Seamless Tube), DIN 17751, VdTÜV 400/12.98.

Welding Products: Filler Metal C-276 - AWS A5.14 / ERNiCrMo-4, Welding Electrode C-276 - AWS A5.11 / ENiCrMo-4.

Others:  ASTM B 366 & ASME SB 366 (Fittings), DIN 17744 (chemical composition).

Chemical Composition

Limiting Chemical Composition, %

Nickel .............................................................................Balance

Molybdenum ...............................................................15.0-17.0

Chromium....................................................................14.5-16.5

Iron..................................................................................4.0-7.0

Tungsten ..........................................................................3.0-4.5

Cobalt ...........................................................................2.5 max.

Manganese ...................................................................1.0 max.

Carbon........................................................................0.01 max.

Vanadium....................................................................0.35 max.

Phosphorus ................................................................0.04 max.

Sulfur ..........................................................................0.03 max.

Silicon .........................................................................0.08 max