Nickel 200 and Nickel 201 are solid solution strengthened, commercially pure  wrought materials with good mechanical properties over a wide range of  temperatures and excellent resistance to many corrosives, in particular  hydroxides. Nickel 201 was a modification of 200 to control carbon (.02 max)  which keeps it from being embrittled by intergranular precipitates at  temperatures of 600° F to 1400° F in many processes. Typically, the elemental  restrictions of both, nickel 200 and nickel 201, are combined into one,  dual-certified chemistry resulting in a single alloy with the desired  characteristics of both alloys, Nickel 200/201.

What are the characteristics of Nickel 200/201?

· Highly resistant to various reducing chemicals

· Excellent resistance to caustic alkalies

· High electrical conductivity

· Excellent corrosion resistance to distilled and natural waters

· Resistance to neutral and alkaline salt solutions

· Excellent resistance to dry fluorine

· Widely used to handle caustic soda

· Good thermal, electrical and magnetostrictive properties

· Offers some resistance to hydrochloric and sulfuric acids at modest  temperatures and concentrations

Both Nickel 200 and 201 offer corrosion resistance in reducing and neutral  media as well as in oxidizing atmospheres provided that the oxidizing media  allows the formation of a passive oxide film. This oxide film accounts for the  materials excellent resistance in caustic environments. Corrosion rates in both  marine and rural atmospheres are very low. The resistance of Nickel 200/201 to  corrosion by distilled and natural waters is excellent. Plus it also gives  excellent service in flowing sea water even at high velocity, but in stagnant or  very low-velocity sea water severe local attack may occur under fouling  organisms or other deposits. In hot water systems where the steam contains  carbon dioxide and air in certain proportions, corrosion rates will be initially  high but will decrease with time if conditions favor the formation of a  protective film.

Nickel 200 is normally limited to service at temperatures below 600° F. At  higher temperatures Nickel 200 products can suffer from graphitization which can  result in severely compromised properties. When operating temperatures are  expected to exceed 600° F, carbon content becomes critical. The lower carbon  content of Nickel 201 makes the material resistant to graphitization and  therefore less subject to embrittlement. Nickel 200 & 201 are approved for  construction of pressure vessels and components under ASME Boiler and Pressure  Vessel Code Section VIII, Division 1. Nickel 200 is approved for service up to  600° F while Nickel 201 is approved for service up to 1230° F. Melting point is  2615-2635° F.

Nickel 200 (UNS N02200) Chemical Composition, %

Nickel 201 (UNS N02201) Chemical Composition, %

In what applications is Nickel 200/201 used?

· Food processing equipment

· Marine and offshore engineering

· Salt production

· Caustic handling equipment

· Manufacture and handling of sodium hydroxide, particularly at temperatures  above 300° F

· Reactors and vessels in which fluorine is generated and reacted with  hydrocarbons

Applications where Nickel 200-201 can be used include chemical processing and  storage, synthetic fiber production, and processes where sodium hydroxide and  fluorine is used. Other applications include aerospace and defense as well as  food processing. Nickel 200/201 has exceptional resistance to caustic alkalies  at various temperatures and concentrations.

Fabrication with Nickel 200/201

All hot working and cold working practices can be utilized when shaping  Nickel 200/201. Hot working temperatures should be between 1200° F and 2250° F  with heavy forming to be performed at temperatures above 1600° F. Annealing  should be performed at a temperature between 1300° F and 1600° F. Care should be  taken when choosing the anneal temperature and time at temperature for this can  greatly influence the mechanical properties and structure of the material.

Nickel 200/201 can be easily welded by conventional welding, brazing, and  soldering processes with the exception of the oxyacetylene process.

For more information on fabrication and machining click here.

Nickel 200/201 ASTM Specifications

Room Temperature properties of Various Products

Mechanical Properties

Room Temperature properties of Various Products