Overview
Nickel is a silvery-white metal known for its corrosion resistance, high melting point,
and ability to form alloys. It is widely used in various applications, particularly in
the production of stainless steel and other alloys. Nickel is also notable for its
magnetic properties and is used in batteries, particularly in rechargeable
nickel-cadmium and nickel-metal hydride batteries.
Grades and Specifications
Nickel is available in various grades, each suited for specific applications. The most
commonly used grades include:
- Nickel 200: Commercially pure nickel with a minimum nickel content
of 99.0%. It has excellent corrosion resistance and is used in chemical processing
and food handling applications.
- Nickel 201: Similar to Nickel 200 but with a lower carbon content,
making it suitable for applications requiring high temperature and corrosive
environments.
- Nickel 300 Series (Inconel): A series of nickel-chromium
superalloys, such as Inconel 600, 625, and 718, known for their high strength and
resistance to oxidation and corrosion.
Specifications:
- ASTM: B162, B191, B366, B443
- ASME: SB162, SB191, SB366, SB443
Chemical Composition
The chemical composition of nickel can vary based on the specific grade. For
Nickel 200, the typical composition is:
| Element |
Composition (%) |
| Nickel (Ni) |
99.0 min |
| Copper (Cu) |
0.5 max |
| Iron (Fe) |
0.4 max |
| Manganese (Mn) |
0.3 max |
| Carbon (C) |
0.02 max |
Mechanical Properties
Nickel exhibits excellent mechanical properties, including strength and ductility.
Typical mechanical properties for Nickel 200 are:
- Tensile Strength: 310 MPa (approx.)
- Yield Strength: 170 MPa (approx.)
- Elongation: 45% (approx.)
- Hardness: 70 HRB (Rockwell B hardness)
Applications
Nickel is used in various industries due to its unique properties:
- Stainless Steel Production: Nickel is a key alloying element in
stainless steel, providing strength, corrosion resistance, and ductility.
- Alloys: Used to create a wide range of high-performance alloys,
including those used in aerospace, marine, and chemical processing applications.
- Batteries: Nickel is used in rechargeable battery technologies,
such as nickel-cadmium (NiCd) and nickel-metal hydride (NiMH) batteries.
- Electroplating: Used for decorative and protective coatings due to
its resistance to corrosion and wear.
- Catalysts: Nickel serves as a catalyst in various chemical
reactions, including hydrogenation processes.
Corrosion Resistance
Nickel is highly resistant to corrosion in a variety of environments, including acidic
and alkaline conditions. It forms a protective oxide layer that helps prevent further
oxidation, making it an ideal choice for applications in harsh environments.
Workability and Fabrication
Nickel is ductile and can be easily formed into various shapes and sizes. Common
fabrication methods include:
- Casting: Nickel can be cast into complex shapes for various
applications.
- Machining: Nickel can be machined with precision, though care must
be taken to avoid work hardening.
- Welding: Nickel can be welded using various techniques, though
specialized procedures may be necessary to maintain corrosion resistance.
Recycling
Nickel is highly recyclable, and recycling operations recover nickel from old alloys,
batteries, and other sources. Recycling nickel conserves natural resources and energy,
reducing the environmental impact associated with mining and processing new nickel.