Cobalt

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Description:

Cobalt is a silver-gray magnetic metal similar to iron and nickel in appearance, but harder and stronger. Cobalt is used in high-temperature creep-resistant super alloys, hard facing and wear-resistant alloys, high-speed steels, tool steels and other steels as well as in cobalt-base tool materials, electrical-resistant alloys, and special expansion and constant-modulus alloys.

Since cobalt is an important trace element in soils it is essential for animal nutrition. Cobalt has unusual coordinating properties, especially the trivalent ion. Cobalt has three radioactive isotopes: cobalt 57, 58 and 60. These radioisotopes are used for biological and medical research.

Crystal Structure: α phase, close-packed hexagonal

- hP2 (P63/mmc); a = 0.25071 nm, c = 0.40686 nm.

                              β phase, face-centered cubic

- cF4 (Fm3m); a = 0.35441 nm,

Minimum Interatomic Distance: β phase, 0.25061 nm 

Atomic Weight: 58.94

Specific Gravity: 8.832 gm/cc for α phase; 8.80 gm/cc for β phase

Melting Point:  1480 oC

Boiling Point:  2900 oC

Heat of Vapor: 93

Heat of Fusion: 3.64

Electrical Conductivity: 0.16

Specific Heat Capacity: 0.099

Hardness: cast, 124 Brinell; electro-deposited, 300 Brinell

Curie Temperature: 1121 oC

Workability: Annealed cobalt strip can be cold rolled to about 25% reduction in area between intermediate anneals.