UNS Number N10276
Other common names: Alloy C276, Hastelloy C, Inconel® C-276
Hastelloy C276 is a nickel-molybdenum-chromium superalloy with an addition of tungsten designed to have excellent corrosion resistance in a wide range of severe environments. The high nickel and molybdenum contents make the nickel steel alloy especially resistant to pitting and crevice corrosion in reducing environments while chromium conveys resistance to oxidizing media. The low carbon content minimizes carbide precipitation during welding to maintain corrosion resistance in as-welded structures. This nickel alloy is resistant to the formation of grain boundary precipitates in the weld heat-affected zone, thus making it suitable for most chemical process application in an as welded condition.
Although there are several variations of the Hastelloy nickel alloy, Hastelloy C-276 is by far the most widely used.
Alloy C-276 is widely used in the most severe environments such as chemical processing, pollution control, pulp and paper production, industrial and municipal waste treatment, and recovery of sour natural gas.
In what forms is Hastelloy C276 Available?
• Bar
• Sheet
• Plate
• Pipe & Tube (welded and seamless)
• Pipe Fittings
• Welding Wire
Corrosion Resistant Hastelloy C276
Considered one of the most versatile corrosion resistant alloys available, Hastelloy C-276 exhibits excellent resistance in a wide variety of chemical process environments including those with ferric and cupric chlorides, hot contaminated organic and inorganic media, chlorine, formic and acetic acids, acetic anhydride, seawater, brine and hypochlorite and chlorine dioxide solutions. In addition, alloy C-276 resists formation of grain boundary precipitates in the weld heat affected zone making it useful for most chemical processes in the as-welded condition. This alloy has excellent resistance to pitting and stress corrosion cracking.
What are the characteristics of Hastelloy C276?
• Excellent corrosion resistance in reducing environments
• Exceptional resistance to strong solutions of oxidizing salts, such as ferric and cupric chlorides
• High nickel and molybdenum contents providing good corrosion resistance in reducing environments
• Low carbon content which minimizes grain-boundary carbide precipitation during welding to maintain resistance to corrosion in heat-affected zones of welded joints
• Resistance to localized corrosion such as pitting and stress-corrosion cracking
• One of few materials to withstand the corrosive effects of wet chlorine gas, hypochlorite and chlorine dioxide
Chemical Composition, %
Ni |
Mo |
Cr |
Fe |
W |
Co |
Mn |
C |
Remainder |
15.0-17.0 |
14.5-16.5 |
4.0-7.0 |
3.0-4.5 |
2.5 max |
1.0 max |
.01 max |
V |
P |
S |
Si |
|
|
|
|
.35 max |
.04 max |
.03 max |
.08 max |
|
|
|
|
In what applications is Hastelloy C-276 used?
• Pollution control stack liners, ducts, dampers, scrubbers, stack-gas reheaters, fans and fan housings
• Flue gas desulfurization systems
• Chemical processing components like heat exchangers, reaction vessels, evaporators, and transfer piping
• Sour gas wells
• Pulp and paper production
• Waste treatment
• Pharmaceutical and food processing equipment
Fabrication with Hastelloy C-276
Hastelloy C-276 alloy can be forged, hot-upset and impact extruded. Although the alloy tends to work-harden, you can have it successfully spun, deep-drawn, press formed or punched. All of the common methods of welding can be used, although the oxyacetylene and submerged arc processes are not recommended when the fabricated item is for use in corrosion service.
Hastelloy C-276 Welding Material
Alloy C276 welding products are used as matching composition filler material for welding C276 alloy wrought and cast products, for dissimilar welding applications including other nickel-chromium-molybdenum alloys and stainless steels, and for weld overlay or cladding of steels.
Specifiacations: ASME-SFA-5.14 ERNiCrMo-4
Forms of C276 Filler Metal Available
• .031 in or .8 mm in diameter
• .035 in or .9 mm in diameter
• .039 in or 1.0 mm in diameter
• .045 in or 1.1 mm in diameter
• .047 in or 1.2 mm in diameter
• .062 in or 1.6 mm in diameter
• .078 in or 2.0 mm in diameter
• .093 in or 2.4 mm in diameter
• .125 in or 3.2 mm in diameter
Filler metals are available in spools and in cut lengths from the above diameters. Straight lengths are available in 36" lengths.
ASTM Specifications
Pipe Smls |
Pipe Welded |
Tube Smls |
Tube Welded |
Sheet/Plate |
Bar |
Forging |
Fitting |
Wire |
B622 |
B619 |
B622 |
B626 |
B575 |
B574 |
B564 |
B366 |
|
Mechanical Properties
Typical Room Temperature Tensile Properties of Annealed Material
Product Form |
Tensile (ksi) |
.2% Yield (ksi) |
Elongation % |
Bar |
110.0 |
52.6 |
62 |
Plate |
107.4 |
50.3 |
67 |
Sheet |
115.5 |
54.6 |
60 |
Tube & Pipe |
105.4 |
45.4 |
70 |