Hastelloy C-276: Chemical Composition, Properties & Corrosion Resistance

← Back to Knowledge Center

Overview

Hastelloy C-276 (UNS N10276 / W.Nr. 2.4819) is a nickel-molybdenum-chromium superalloy with the addition of tungsten. It is widely recognized as one of the most versatile corrosion-resistant alloys available today. Hastelloy C-276 was designed to offer exceptional resistance to a wide variety of chemical process environments, including strong oxidizers such as ferric and cupric chlorides, chlorine, hot contaminated media (organic and inorganic), formic and acetic acids, acetic anhydride, seawater, and brine solutions. The low carbon content minimizes carbide precipitation during welding, maintaining corrosion resistance in the as-welded condition.

Chemical Composition (ASTM B575)

The carefully balanced composition of Hastelloy C-276 provides the alloy with its exceptional corrosion resistance. The high nickel and molybdenum contents provide resistance to reducing environments, while the chromium content provides resistance to oxidizing conditions. The low carbon content (≤0.01%) is critical for maintaining corrosion resistance in welded structures.

Element	Min %	Max %
Nickel (Ni)	Balance	Balance
Molybdenum (Mo)	15.0	17.0
Chromium (Cr)	14.5	16.5
Iron (Fe)	4.0	7.0
Tungsten (W)	3.0	4.5
Cobalt (Co)	—	2.5
Manganese (Mn)	—	1.0
Carbon (C)	—	0.01
Silicon (Si)	—	0.08
Vanadium (V)	—	0.35
Phosphorus (P)	—	0.04
Sulfur (S)	—	0.03

Physical Properties

Hastelloy C-276 has a face-centered cubic (FCC) crystal structure, which contributes to its excellent ductility and formability. The alloy's thermal properties are well-suited for high-temperature chemical process equipment.

Property	Value	Unit
Density	8.89	g/cm3
Melting Point	1370	°C
Specific Heat (21°C)	427	J/kg·K
Thermal Conductivity (21°C)	11.1	W/m·K
Electrical Resistivity (21°C)	1.25	μΩ·m
Modulus of Elasticity (21°C)	205	GPa
Mean Coefficient of Thermal Expansion (21-93°C)	11.2	μm/m·°C

Mechanical Properties at Room Temperature

The mechanical properties of Hastelloy C-276 vary depending on the product form and heat treatment condition. The data below represents typical values for solution-annealed plate and sheet per ASTM B575.

Property	Value
Tensile Strength	790 MPa (115 ksi)
Yield Strength (0.2% offset)	355 MPa (51 ksi)
Elongation in 2 inches	50%
Hardness (Rockwell B)	87 HRB
Impact Strength (Charpy V-notch, room temp)	280 J

High-Temperature Mechanical Properties

Hastelloy C-276 maintains excellent strength at elevated temperatures, making it suitable for high-temperature chemical process equipment. The alloy can be used in continuous service up to approximately 1100°C (2000°F) in oxidizing environments, and even higher in reducing environments.

Temperature (°C)	Tensile Strength (MPa)	Yield Strength (MPa)	Elongation (%)
21 (Room)	790	355	50
316	710	310	52
427	690	290	50
538	650	270	48
649	580	250	50
760	450	220	55
871	310	190	65

Corrosion Resistance

Hastelloy C-276 is renowned for its exceptional corrosion resistance in a wide range of aggressive environments. The combination of high nickel, molybdenum, and chromium contents provides outstanding resistance to both oxidizing and reducing conditions.

Resistance to Specific Media:

• Wet Chlorine Gas: Exceptional resistance to wet chlorine gas and hypochlorite solutions, making it the material of choice for chlor-alkali plants and bleach manufacturing facilities.
• Oxidizing Chloride Salts: Highly resistant to ferric chloride, cupric chloride, and other oxidizing chloride salts. Widely used in pickling operations and chemical processing equipment.
• Organic and Inorganic Acids: Excellent resistance to formic acid, acetic acid, acetic anhydride, citric acid, and fatty acids. Resistant to hot, contaminated sulfuric and phosphoric acids.
• Seawater and Brine: Highly resistant to pitting and crevice corrosion in seawater at elevated temperatures. Suitable for marine heat exchangers and desalination equipment.
• Sulfuric Acid: Excellent resistance to sulfuric acid at concentrations up to 60% and temperatures up to 80°C. One of the best alloys for sulfuric acid service.
• Hydrochloric Acid: Good resistance to hydrochloric acid at moderate concentrations and temperatures. Superior to most stainless steels in this environment.

Applications

The exceptional corrosion resistance of Hastelloy C-276 makes it the material of choice for the most demanding chemical process environments:

• Chemical Processing: Reactors, heat exchangers, distillation columns, and piping systems handling aggressive chemicals including chlorine, ferric chloride, and sulfuric acid.
• Pollution Control: Flue gas desulfurization (FGD) scrubbers, stack liners, and ducting. The alloy withstands the corrosive conditions of wet SO2 and chloride-containing flue gases.
• Pulp and Paper: Digesters, bleaching towers, and black liquor recovery boilers. The alloy resists the aggressive chloride and sulfur environments in pulp processing.
• Pharmaceutical: Reaction vessels, crystallizers, and filtration equipment for active pharmaceutical ingredient (API) production. The alloy meets FDA requirements for cleanability.
• Oil and Gas: Sour gas (H2S) production equipment, downhole tools, and wellhead components. The alloy resists sulfide stress cracking and chloride pitting.
• Waste Treatment: Incinerators, scrubbers, and ash handling systems. The alloy withstands the highly corrosive conditions of combustion products and waste treatment chemicals.

Available Product Forms

Hangbo Alloy Group manufactures and supplies Hastelloy C-276 in the following product forms, conforming to ASTM, ASME, and NACE specifications:

• Plates & Sheets: ASTM B575, ASME SB-575, thicknesses from 0.5 mm to 50 mm, hot-rolled or cold-rolled, solution annealed.
• Round Bars: ASTM B574, ASME SB-574, diameters from 6 mm to 300 mm, hot-finished or cold-drawn.
• Seamless Tubes & Pipes: ASTM B622, ASTM B619, ASME SB-622, sizes from 6 mm OD to 219 mm OD.
• Forgings: ASTM B564, ASME SB-564, custom flanges, rings, and fittings per customer drawing.
• Welding Wire: AWS A5.14 ERNiCrMo-4, diameters 0.8 mm to 5.0 mm, precision-wound coils.

Related Standards

Standard	Description
ASTM B575	Plate, Sheet, and Strip
ASTM B574	Bar and Rod
ASTM B622	Seamless Pipe and Tube
ASTM B619	Welded Pipe
ASTM B564	Forgings
ASTM B366	Fittings
ASME SB-575	Boiler and Pressure Vessel Code
NACE MR0175	Sour Gas Service

Contact Us for Hastelloy C-276

Hangbo Alloy Group maintains extensive inventory of Hastelloy C-276 in all standard product forms. We provide mill test certificates, third-party inspection reports (SGS, TUV), and custom processing services including cutting, machining, and surface finishing.

For quotations, material certifications, or technical consultation, contact our sales team or call +86-136-1165-6360. We typically respond within 10 minutes.