Nickel Alloy Plate

Sandmeyer Steel Company stocks Alloy C276 nickel alloy plate in thicknesses from 3/16" (4.8mm) through 2 ½" (63.5mm) and is one of the most universally corrosion-resistant materials available for applications such as chemical and petrochemical processing, flue gas desulfurization, pulp and paper equipment, industrial waste, and air pollution control.

Available thicknesses for Alloy C276:

3/16" 1/4" 3/8" 1/2" 5/8" 3/4"
4.8mm 6.3mm 9.5mm 12.7mm 15.9mm 19mm
 
1" 1 1/4" 1 1/2" 1 3/4" 2" 2 1/2"
25.4mm 31.8mm 38.1mm 44.5mm 50.8mm 63.5mm

Alloy C276 nickel alloy plate (UNS N10276) is a nickel-molybdenum-chromium-iron-tungsten alloy which is among the most corrosion-resistant alloys currently available. 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 welding joints.

Alloy C276 nickel alloy plate also has good high temperature strength and moderate oxidation resistance although the alloy will eventually form embrittling high temperature precipitates.

Specification Sheet Overview

for Alloy C276 (UNS N10276)
W. Nr. 2.4819:
A Nickel-Molybdenum-Chromium Alloy with Excellent Corrosion Resistance in both Oxidizing and Reducing Environments

Alloy C276 (UNS N10276)

General Properties

Alloy C276 nickel alloy plate (UNS N10276) is an austenitic nickel-molybdenum-chromium alloy with a small addition of tungsten. It is one of the premier corrosion resistant materials available for process industries. Alloy C276 nickel alloy plate has excellent corrosion resistance in both oxidizing and reducing environments.

The combination of the high molybdenum and chromium content, along with the addition of tungsten, make Alloy C276 nickel alloy plate highly resistant to chloride stress corrosion cracking, pitting, crevice corrosion and general corrosion.

Alloy C276 nickel alloy plate can operate in oxidizing atmospheres up to 1900oF (1038oC), however, the alloy lacks sufficient chromium content to operate successfully in the most strongly oxidizing environments like hot, concentrated nitric acid.

The low carbon content of Alloy C276 nickel alloy plate enables the alloy to be utilized in the as-welded condition. It cannot be hardened by heat treatment, but can be hardened by cold working. The alloy has a higher work-hardening rate than the austenitic stainless steels which should be taken into consideration.

Alloy C276 nickel alloy plate can be easily welded and processed utilizing standard shop fabrication practices for austenitic stainless steels and nickel based alloys.


Chemical Analysis

Weight % (all values are maximum unless a range is otherwise indicated)

Nickel Balance Manganese 1.0
Molybdenum 15.0 min.-17.0 max. Carbon 0.01
Chromium 14.5 min.-16.5 max. Vanadium 0.35
Iron 4.0 min.-7.0 max. Phosphorous 0.04
Tungsten 3.0 min.-4.5 max. Sulfur 0.03
Cobalt 2.5 Silicon 0.08

Physical Properties

Density

0.321 lbs/in3
8.89 g/cm3

Specific Heat

0.102 BTU/lb-°F (70°F)
427 J/kg-°K (20°C)

Modulus of Elasticity

29.8 x 106 psi
205.0 GPa

 

Thermal Conductivity 212°F (100°C)

67 BTU/hr/ft2/ft/°F
9.8 W/m-°K

Melting Range

2415 – 2500°F
1325 – 1370°C

Electrical Resistivity

51 Microhm-in at 75°C
1.30 Microhm-cm at 24°C
Mean Coefficient of Thermal Expansion
Temperature Range
°F °C in/in/°F cm/cm°C
200 93 6.8 x 10-6 12.24 x 10-6
400 204 7.0 x 10-6 12.60 x 10-6
600 316 7.2 x 10-6 12.96 x 10-6
800 427 7.4 x 10-6 13.32 x 10-6
1000 538 7.8 x 10-6 14.0 x 10-6
1200 649 8.2 x 10-6 14.8 x 10-6
1400 760 8.5 x 10-6 15.3 x 10-6
1600 871 8.8 x 10-6 15.8 x 10-6
1700 927 9.0 x 10-6 16.2 x 10-6

Mechanical Properties

Typicals Values at 68°F (20°C)

Yield Strength
0.2% Offset
Ultimate Tensile
Strength
Elongation
in 2 in.
Hardness
psi (min.) (MPa) psi (min.) (MPa) % (min.) (max.)
41,000 283 100,000 690 40 100 Rockwell B

Corrosion Resistance

Alloy C276 nickel alloy plate is one of the premier corrosion resistant materials that performs exceptionally well in both oxidizing and reducing environments. It resists chloride stress corrosion cracking, pitting, crevice and general corrosion. The alloy is also resistant to carbide precipitation during welding enabling it to be utilized in the as-welded condition.

In chemical processing applications, the alloy has exceptional resistance to sulfuric, hydrochloric, formic, acetic and phosphoric acids. Alloy C276 nickel alloy plate performs well in environments containing acid chlorides, solvents and acetic anhydride, The alloy is one of the few grades that withstands wet chlorine gas, hypochlorite and chlorine dioxide solutions.

Alloy C276 nickel alloy plate is highly resistant to concentrated solutions of oxidizing salts including iron and copper chloride. It also performs well in seawater, especially under crevice conditions where other frequently used alloys such as stainless steel, Alloy 400 and Alloy 625 fail.

The operating conditions of flue gas desulfurization systems offer a challenging environment for corrosion resistant materials. Scrubber liquors and gas condensates often contain chlorides. Alloy C276 nickel alloy plate nickel alloy plate has been shown to withstand higher chloride levels than other grades before the onset of localized corrosion in these systems.

Alloy C276 nickel alloy plate is used extensively in the recovery and processing of sour natural gas which contains hydrogen sulfide along with carbon dioxide and chlorides. Carbon and alloy steels cannot withstand this corrosive environment. They are subject to failure by sulfide stress cracking or stress corrosion cracking. The rich chemistry of Alloy C276 nickel alloy plate makes it resistant to sour environments even at high temperatures in deep wells.

Comparitive behavior of NiCR-MO alloys in sulfuric acid.

Isc-corrosion chart for Alloy C-276 in phosphoric acid.

Iso-corrosion chart for Alloy C-276 in hydrochloric acid.Maximum depth of attack by crevice corrosion after exposure to quiescent seawater at 85°F (29°) for 180 days as a function of PREN

Corrosion Tests* in Hydrogen Fluoride Gas.

Test Duration, 36 Hours. Temperature 932-1112°F (500-600°C)

MATERIAL Corrosion Rate, mpy (mm/a) Comments
Alloy C-276 0.3 (0.01) Iridescent tarnish film
Alloy 600 0.7 (0.02) Iridescent tarnish film
Nickel 200 9 (0.23) Black film
Nickel 201 14 (0.36) Black film
Alloy 400 13 (0.33) Adherent dark film
Alloy K-500 16 (0.41) Adherent dark film
70/30 Copper-Nickel 16 (0.41) Adherent dark film

* 7 lb HF per hour at 4 psig was passed through a laboratory furnace for hydroflourination of metal oxides

Corrosion-resistance of nickel alloys in four 24-hour tests in boiling acetic acid

Alloy Ni Cr Mo W Nb N PREN
316 Stainless Steel 12 17 2.2 20.4
317 Stainless Steel 13 18 3.8 23.7
Alloy 825 42 21.5 3 26.0
Alloy G-3 44 22 7 32.5
Alloy 25-6MO 25 20 6.5 0.20 35.8
Alloy 625 62 22 9 3.5 40.8
Alloy C-276 58 16 16 3.5 45.2
Alloy 622 60 20.5 14 3.5 46.8
Alloy 686 58 20.5 16.3 3.5 50.8

* (Pren) = %CR + 1.5 (%Mo + %W + %Nb) + 30 (%N)

Maximum Pitting or Crevice Attack, mils (MM), in FGD Scrubber Slurrya

Alloy Quencher Absorber Absorber
Outlet
Outlet
Duct
Bypass
Duct
316L Stainless Steel 22 (0.56) 21 (0.53) 35 (0.89)b 35 (0.89)b 12 (0.30)
317LM Stainless Steel 20 (0.51) 22 (0.56) 29 (0.74) 33 (0.84) 29 (0.74)
Alloy 825 15 (0.38) 33 (0.84) 39 (0.99) 50 (1.27)b 10 (0.25)
Alloy 625 <2 (<0.05) 10 (0.25) 11 (0.28) 7 (0.18) nil
Alloy C-276 nil nil <2 (<0.05) nil nil

a 6-month exposure at 126°F (62°C), pH 5.5, 5000 ppm chlorides
b Perforated.

Fabrication Data

Alloy C276 nickel alloy plate can be easily welded and processed utilizing standard shop fabrication practices for austenitic stainless steels and nickel based alloys.

Hot Forming

The hot-working temperature range for Alloy C276 nickel alloy plate is 1600 – 2250°F (870 – 1230°C). The alloy should be water quenched after hot working. Heat treatment is recommended after hot working to ensure maximum corrosion resistance.

Cold Forming

Alloy C276 nickel alloy plate should be in the annealed condition for cold working. The alloy has a higher work-hardening rate than the austenitic stainless steels which should be taken into consideration. An in-process anneal may be necessary with a high degree of cold working. If the alloy undergoes greater than 15% deformation during cold working, a solution anneal may be necessary.

Welding

Alloy C276 nickel alloy plate can be readily welded by most standard processes including GTAW (TIG), PLASMA, GMAW (MIG/MAG) and SMAW (MMA). A post weld heat treatment is not necessary. Brushing with a stainless steel wire brush after welding will remove the heat tint and produce a surface area that does not require additional pickling.

Machining

Alloy C276 nickel alloy plate should preferably be machined in the annealed condition. Since Alloy C276 nickel alloy plate is prone to work–hardening, only low cutting speeds should be used and the cutting tool should be engaged at all times. Adequate cut depth is necessary to assure avoiding contact with the previously formed work-hardened zone.

NOTE: The information and data in this product data sheet are accurate to the best of our knowledge and belief, but are intended for informational purposes only, and may be revised at any time without notice. Applications suggested for the materials are described only to help readers make their own evaluations and decisions, and are neither guarantees nor to be construed as express or implied warranties of suitability for these or other applications.

Associations and Accreditations

ASME
ASME MO Certified
Metals Service Center Institute Member 2016
NIAC
SSINA
Quality System Certificate
Pennsylvania Prosperity Project
Proud Member of the National Association of Manufacturers