Nickel 201 (Lower Carbon Nickel 200)

Nickel 201 - UNS N02201 - Ni201 - Pure Nickel

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Table of Contents
Datasheet Chemistry
Inventory Applications
General Data Mechanical Properties
Specifications Physical Properties & Application Data
Machining, Welding, & Processing References

The Nickel 201 alloys is an alloy that contains commercially pure wrought Nickel and has good mechanical properties that extend over a wide range of temperatures. The Nickel alloy 201 has excellent resistance to many corrosives, hydroxides in particular.

Nickel 201 has native properties to provide strong resistance to corrosion in acids and alkalis. It is especially useful under reducing conditions. The alloy has outstanding resistance to caustic alkalis, which includes its molten state. The alloy shows good resistance in acid, alkaline, and neutral salt solutions.

However, when Nickel 201 is in oxidizing salt solutions severe corrosion will occur. The Nickel 201 alloy is resistant to all dry gases at room temperature. In dry chlorine and hydrogen chloride, Nickel 201 alloy may be used in temperatures up to 550 °C. Its resistance to mineral acids varies according to temperature, concentration, and solution aeration. Its corrosion resistance displays better in de-aerated acid.


View or download Special Metals' Ni200/201 datasheet here


Min% Max%
Ni 99.0
C 0.02
Mn 0.35
Cu 0.25
S 0.01
Si 0.35
Fe 0.40
*Composition information provided by Special Metals' datasheet on alloy 201, available here.

Typical Inventory

Round Bar, Plate, Tubing, Pipe, Fastener


  • Manufacture and handling of sodium hydroxide, particularly at temperature above 300 °C.
  • Production of viscose rayon. Manufacturing of soap.
  • Analine hydrochloride production and in the chlorination of aliphatic hydrocarbons such as benzene, methane and ethane.
  • Manufacturing of vinyl chloride monomer.
  • Reactors and vessels in which fluorine is generated and reacted with hydrocarbons

General Data

  • Nickel 201 displays good corrosion resistance in acids and alkalis and is most useful under reducing conditions.
  • Outstanding resistance to caustic alkalis, which includes its molten state. The alloy shows good resistance in acid, alkaline, and neutral salt solutions.
  • Caution: in oxidizing salt solutions, severe corrosion will occur with this alloys
  • This alloy is virtually immune to inter granular attack above 315 °C. However, chlorates must be kept to a minimum.

Mechanical Properties

The typical properties listed can usually be provided in rounds, sheet, strip, plate, & custom forgings. We have the equipment to produce small quantities in special sizes to meet our customers’ specific needs. The table below shows Special Metals' Nominal Mechanical Properties of Alloy 201. For most common forms and exceptions, check out the datasheet linked underneath the table.

Form Cond. UTS ksi (MPa) YS 0.2% OS ksi (MPa) Elong. % in 2 in. Hardness
Rod & Bar HF & HF, Ann. 50-60 (345-415) 10-25 (70-170) 60-40 75-100 BHN
Rod & Bar Cold Drawn 60-100 (415-690) 35-90 (240-620) 35-10 125-200 BHN
Rod & Bar Cold Drawn, Ann. 50-60 (345-415) 10-25 (70-170) 60-40 75-100 BHN
Plate Hot Rolled 50-70 (345-485) 12-35 (83-240) 60-35 NA
Plate Hot Rolled, Ann. 50-70 (345-485) 12-35 (83-240) 60-40 NA

UTS = Ultimate Tensile Strength, YS = Yield Strength, OS = Offset, HF = Hot Finished, CD = Cold Drawn, Ann. = Annealed, NA = Not Available, BHN = Brinell Hardness Number

Link to Special Metals' datasheet/technical bulletin on alloy 200 & 201

Common Specifications

Note that the specifications listed are common for this alloy but are for reference only and may be specific to a certain form. The specifications listed are not comprehensive nor indicative of any edition, revision, or similar such as an amendment. Please, reach out to our sales department to request the Material Test Report (MTR) or to confirm your required specifications.

Form Standard
Identification UNS N02201, DIN 17740, DIN 17750 – 17754, W. Nr. 2.4061 and W. Nr. 2.4068
Bar ASTM B160, ASME SB160
Sheet, Plate, or Strip AMS 5553, ASTM B162, ASME SB162
Pipe - Seamless ASTM B161, ASME SB161
Tube - Seamless ASTM B161, ASTM B163, ASME SB161, ASME SB163
Tube - Welded ASTM B730, ASTM B751, ASME SB730, ASME SB751
Fitting ASTM B366, ASME SB366
Forging ASTM B564, ASME SB564
Weld Wire Nickel FM 61/ UNS N02061/ W. Nr. 2.4155/ AWS A5.14 ERNi-1/ ASME IX F-No. 41
Weld Electrode Nickel FM 141/ UNS W82141/ W. Nr. 2.4156/ AWS A5.11 ENi-1/ ASME IX F-No. 41

Physical Properties

Density 8.9 g/cm cube
Specific Heat 440 J/kg K
Electrical Resistivity 8.5 micro ohms cm
Curie Temperature 358 °C
Melting Range 1435-1445 °C
Thermal Expansion (106K) 14.3 (20-300 °C)


Nickel and cobalt based alloys can be difficult to machinine. However, it should be emphasized that these alloys can be machined using conventional production methods at satisfactory rates. These alloys harden rapidly, generate high heat during cutting, weld to the cutting tool surface and offer high resistance to metal removal because of their high shear strengths. The following are key points which should be considered during machining operations:

  • CAPACITY - Machine should be rigid and overpowered as much as possible.
  • RIGIDITY - Work piece and tool should be held rigid. Minimize tool overhang.
  • TOOL SHARPNESS - Make sure tools are sharp at all times. Change to sharpened tools at regular intervals rather than out of necessity. A 0.015 inch wear land is considered a dull tool.
  • TOOLS - Use positive rake angle tools for most machining operations. Negative rake angle tools can be considered for intermittent cuts and heavy stock removal. Carbide-tipped tools are suggested for most applications. High speed tools can be used, with lower production rates, and are often recommended for intermittent cuts.
  • POSITIVE CUTS - Use heavy, constant, feeds to maintain positive cutting action. If feed slows and the tool dwells in the cut, work hardening occurs, tool life deteriorates and close tolerances are impossible.
  • LUBRICATION - lubricants are desirable. Soluble oils are recommended especially when using carbide tooling.

Link to Ni200.


Link to Special Metals' datasheet/technical bulletin on alloy 200 & 201

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