Nickel Alloy 22 | UNS N06022 | 2.4602 | Hastelloy C-22

Shaanxi Shangyou Stainless Steel Co., Ltd. supplies Nickel Alloy 22, also known as Hastelloy C-22, identified as UNS N06022 and Werkstoff 2.4602, in plate, sheet, strip, round bar, rod, seamless and welded tubing, pipe, wire, and forging forms. Our Alloy 22 products can be supplied according to ASTM B575 / ASME SB-575 for plate, sheet and strip; ASTM B574 / ASME SB-574 for bar and wire; ASTM B622 / ASME SB-622 for seamless pipe and tube; ASTM B619 / ASME SB-619 for welded pipe; and ASTM B564 / ASME SB-564 for forgings.

Nickel Alloy 22 is a fully austenitic, versatile nickel-chromium-molybdenum-tungsten alloy with controlled iron content, designed for extreme corrosion resistance. The high chromium content (20-22.5%) provides excellent resistance to oxidizing media such as nitric acid, while the molybdenum (12.5-14.5%) and tungsten (2.5-3.5%) offer outstanding resistance to reducing media such as sulfuric and hydrochloric acids. This combination, along with a low carbon content (0.015% max), makes Alloy 22 particularly effective in environments containing mixed acids and acid-halides, where both oxidizing and reducing conditions may occur. The alloy exhibits exceptional resistance to pitting, crevice corrosion, intergranular attack, and stress corrosion cracking, and is approved for sour service per NACE MR0175 / ISO 15156-3.

Alloy 22 is normally supplied in the annealed condition. The standard annealing treatment is performed at approximately 1,065 – 1,120°C (1,950 – 2,048°F), followed by rapid cooling to avoid detrimental phase precipitation and maintain corrosion resistance. This treatment provides optimal ductility and corrosion resistance. The alloy is not age-hardenable and is strengthened only through cold working.

Alloy 22 is not age-hardenable – strength increases only through cold working. Annealed material typically exhibits tensile strength of 690 – 860 MPa (100 – 125 ksi), while spring temper can achieve 1,379 – 1,655 MPa (200 – 240 ksi). The alloy naturally prevents the development of grain boundary precipitates during processing, making it very weldable and versatile.

Alloy 22 is widely regarded as one of the most versatile corrosion-resistant nickel alloys available, offering outstanding resistance to a broad range of aggressive media.

• Superior resistance to pitting and crevice corrosion, particularly in acid-halide environments.
• Excellent resistance to stress corrosion cracking in chloride environments.
• Resistance to both oxidizing and reducing media: high chromium content resists oxidizing conditions (nitric acid, ferric/cupric chlorides); molybdenum and tungsten provide resistance to reducing media (sulfuric acid, hydrochloric acid).
• Outstanding performance in mixed acid systems containing nitric, sulfuric, hydrochloric, and phosphoric acids.
• Excellent resistance to wet chlorine gas, hypochlorite and chlorine dioxide solutions.
• Good resistance to seawater under both stagnant and flowing conditions.
• High-temperature resistance: resists oxidation, carburization, sulfidation, and halide attack at elevated temperatures.
• Low carbon content minimizes sensitization and intergranular attack in the weld heat-affected zone.
• Approved for sour service per NACE MR0175 / ISO 15156-3.

• For applications requiring even higher resistance to reducing conditions, Alloy C-276 may be considered.
• While Alloy 22 is among the most versatile corrosion-resistant alloys, final selection must consider the specific medium, concentration, temperature, and exposure conditions.

• Chemical Processing: Reactors, heat exchangers, piping systems, pressure vessels, pumps, valves for aggressive acid environments.
• Pollution Control: Flue gas desulfurization (FGD) scrubbers, waste incineration, sewage treatment equipment.
• Oil and Gas: Sour gas environments, offshore components.
• Pharmaceutical and Biotech: High-purity process equipment.
• Pulp and Paper: Bleaching equipment.
• Nuclear: Fuel reprocessing, radioactive waste handling.
• Marine: Seawater-cooled heat exchangers, seawater industrial equipment.

Available quality-control services include:

• Heat-number traceability
• Chemical composition verification
• Tensile, yield and elongation testing
• Hardness inspection
• Dimensional and surface inspection
• Positive Material Identification (PMI)
• Ultrasonic testing
• Dye penetrant inspection
• Heat-treatment records
• EN 10204 3.1 material certificate

For an accurate quotation, please provide:

Alloy Grade · Standard · Product Form · Dimensions · Quantity · Heat Treatment · Inspection Requirement · Application · Working Temperature · Destination Port

For corrosive environments, also provide:

Chemical Medium · Concentration · Temperature · Oxidizing or Reducing Conditions

• Request Nickel Alloy 22 Quote
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Nickel Alloy 22 (UNS N06022), also known as Hastelloy C-22, is a versatile nickel-chromium-molybdenum-tungsten alloy designed for extreme corrosion resistance, with excellent performance in both oxidizing and reducing environments.

The UNS designation is N06022; the European Werkstoff number is 2.4602; the EN material symbol is NiCr21Mo14W.

ASTM B575 / ASME SB-575 applies to plate, sheet and strip; ASTM B574 / ASME SB-574 applies to bar, rod and wire.

ASTM B622 / ASME SB-622 for seamless pipe and tube; ASTM B619 / ASME SB-619 for welded pipe; ASTM B626 / ASME SB-626 for welded tube.

No. Alloy 22 is not age-hardenable and is strengthened only through cold working.

It resists oxidizing acid chlorides, wet chlorine, nitric acid, sulfuric acid, hydrochloric acid, formic acid, acetic acid, ferric and cupric chlorides, seawater, brine, and many mixed or contaminated chemical solutions.

Yes. Alloy 22 provides excellent resistance to chloride stress-corrosion cracking and is considered highly resistant in most chloride environments.

Alloy 22 has higher chromium content (20-22.5% vs 14.5-16.5%) and is designed for enhanced resistance to oxidizing media and mixed acids. Alloy C-276 has higher molybdenum (15-17%) and is more suited for reducing acid environments.

Yes. Alloy 22 exhibits excellent weldability with minimal risk of sensitization or intergranular attack. Suitable processes include gas tungsten arc (GTAW), shielded metal arc (SMAW), and gas metal arc (GMAW).

Please provide the standard, product form, dimensions, quantity, heat-treatment condition, inspection requirements, application, working temperature and destination port. For corrosive environments, also specify the chemical medium and concentration.