Nickel Alloys Inco Alloy C-276

Product Data Sheet – Nickel Alloys

Inco Alloy C-276 UNS-N10276

Inco alloy C-276 is a nickel, chromium, molybdenum, tungsten alloy designed for outstanding corrosion resistance in a wide range of severe environments. This alloy is non magnetic, single phase and has good strength and ductility.

Chemical Composition of Nickel Alloy C-276

ASTM B574 – Rod

Nickel	Chromium	Molybdenum	Iron	Tungsten	Cobalt	Carbon	Manganese	Silicon	Phosphorus	Sulphur	Vanadium
~ 60%	14.5-16.5	15.0-17.0	4.0-7.0	3.00-4.50	2.5 max	0.010 max	1.0 max	0.08 max	0.04 max	0.03 max	0.35 max

Equivalent Specifications

Country	Body	Grade
USA	UNS	N10276
France	AFNOR	NC 17 D
GB	BS	–
Germany	DIN	2.4819

ASTM Product Specifications

Specification	Title
B366	Nickel & Nickel Alloy Fittings
B564	Nickel Alloy Forgings
B574	Low Carbon Nickel Molybdenum Chromium, Low Carbon Nickel Chromium Molybdenum and Low Carbon Nickel Chromium Molybdenum Tungsten Alloy Rod
B575	Low Carbon Nickel Molybdenum Chromium, Low Carbon Nickel Chromium Molybdenum and Low Carbon Nickel Chromium Molybdenum Tungsten Alloy Plate, Sheet and Strip
B619	Welded Nickel & Nickel Cobalt Alloy Pipe
B622	Seamless Nickel & Nickel Cobalt Alloy Pipe
B626	Welded Nickel & Nickel Cobalt Alloy Tube
B751	General requirements for Nickel & Nickel Alloy Welded Tube
B775	General requirements for Nickel & Nickel Alloy Welded Pipe

Specified Minimum Mechanical Properties

ASTM B574 – Rod

	0.2% Proof Stress	Tensile Strength	Elongation
Product	MPa	MPa	%
B574 Minimum	283	690	40
Typical	415	790	50

Availability of Nickel Alloy C-276

Austral Wright Metals can supply this C276 alloy as plate, sheet and strip, rod and bar, seamless and welded tube and pipe, welding fittings, forgings and forging stock.

Description

Inco C-276 is a nickel chromium molybdenum tungsten alloy designed for corrosion resistance in a wide variety of severe environments. The alloy has good strength and ductility, and can be used at elevated temperatures. It can not be hardened by heat treatment but will harden by cold work. In the annealed condition it is strengthened by solid solution hardening with nickel, chromium, molybdenum and tungsten. C-276 has outstanding corrosion resistance in sulphuric and hydrochloric acids, & the nickel level gives near immunity to stress corrosion cracking.

Typical Applications for Nickel Alloy C-276

Used in severe environments in chemical processing, pollution control, pulp and paper manufacture, treatment of industrial wastes and municipal waste. Applications in chemical processing include heat exchangers, reaction vessels, evaporators and process piping. In air pollution control: stack liners, ducts, dampers, scrubbers, stack gas reheaters, fans and fan housings. In sour gas recovery Inco C-276 delivers a high level of performance in various down hole and surface components, including tubing, coupling and subsurface valves.

Physical Properties of Nickel Alloy C-276

Property	Metric Units
Melting Range	1325-1370°C

Density	8,820 kg/m³ @ 20°C

Coefficient of Thermal Expansion	12.2 x 10 ^-6 / °C (20°C)
Themal Conductivity	9.8 W/m. °C @ 20°C
Thermal Capacity (Specific Heat)	427 J/kg. °C @ 20°C

Electrical Resistivity	1.3 microhm.m @ 20°C

Modulus of Elasticity (tension)	205 GPa @ 20°C
Modulus of Rigidity (torsion)	79 GPa @ 20°C
Poisson’s Ratio	0.307

Magnetic Permeability	1.0002 @ 200 Oe

Corrosion Resistance of Nickel Alloy C-276

Outstanding corrosion resistance is the major attribute of C-276. The alloy resists general corrosion, stress corrosion cracking, pitting and crevice corrosion in a wide range of aggressive environments. It has very low carbon content, and in most media can be used as welded without loss of corrosion resistance. C-276 has exceptional resistance to many of the most severe media in chemical processing. Including highly oxidising neutral and acid chlorides, solvents, formic and acetic acids, acetic anhydride, wet chlorine gas, hypochlorites and chlorine solutions.

In flue gas desulphurisation applications C-276 outperforms many other alloys

Maximum pitting or crevice attack, mm in FGD scrubber slurry

(6 months at 52°C, pH 5.5, 5000 ppm chlorides)

Alloy	Quencher	Absorber	Absorber Outlet	Outlet Duct	Bypass Duct
316L	0.56	0.53	0.89	0.89	0.30
317LM	0.51	0.56	0.74	0.84	0.74
Incoloy 825	0.38	0.84	0.99	1.27	0.25
Incoloy 625	< 0.05	0.25	0.28	0.18	nil
Inco C-276	nil	nil	< 0.05	nil	nil


Variation of tensile properties with temperature		Corrosion rates in hydrochloric acid

Fabrication

Inco C-276 is readily fabricated by standard methods. Work hardening in cold forming may require intermediate annealing. Heavy forces are required for both hot and cold forming due to the high strength of C-276.

Machinability

Inco C-276 is classed as a “D-2” alloy as it is difficult to machine. Heavy machines, sharp tools, slow speeds and deep, continuous cuts to remove the work hardened layer are needed.

Heat Treatment

Inco C-276 is annealed at 1150 – 1175oC and water quenched. Please consult Austral Wright Metals for specific advice.

Weldability

Inco C-276 is readily welded by GMAW (MIG), GTAW (TIG), SMAW (manual) and SAW processes. Preheat, post heat and post weld heat treatment are not needed. Clean the parent material to avoid contamination of the weld pool.

Welding Consumables

	Normal Service	Higher Strength	Best Corrosion Resistance
Welding Electrode	Inconel WE C-276	Inco Weld WE 686CPT	Inco Weld WE 686CPT
Filler Metal	Inconel FM C276	Inco FM 686CPT	Inco Weld FM 686CPT
Flux Cored Wire	N/A	N/A	N/A

The technical advice and recommendations made in this Product Data Sheet should not be relied or acted upon without conducting your own further investigations, including corrosion exposure tests where needed. Please consult current editions of standards for design properties. Austral Wright Metals assumes no liability in connection with the information in this Product Data Sheet. Austral Wright Metals supplies a comprehensive range of stainless steels, copper alloys, nickel alloys and other high performance metals for challenging service conditions. Our engineers and metallurgists will be pleased to provide further data and applications advice.