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Cobalt ( Co )

Material Information

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Foil Lump Microfoil Powder Rod Single Crystal Sputtering Target Wire
Foil Lump Microfoil Powder Rod Single Crystal Sputtering Target Wire

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General Description:  

Discovered in 1735 by G. Brandt in Stockholm, Sweden.

Cobalt is a hard, grey metal which is ferromagnetic. It is usually found in association with nickel in arsenical ores, its abundancy in the Earth's crust being 20 ppm. Cobalt is relatively unreactive, being stable in air and only slowly attacked by dilute acids. It does not combine with hydrogen and nitrogen but it does react with carbon, oxygen and steam at elevated temperatures, producing CoO in the latter cases.

Cobalt salts (primarily cobalt aluminate, known as "Cobalt Blue", or "Thenard's Blue") have been known of and used for centuries to provide a blue coloration to paints and ceramics. Cobalt alloys have good thermal and oxidation resistance, coupled with mechanical strength. The metal is also used in electroplating and its radioactive isotope, 6OCobalt, is used in the treatment of cancer.

   

Atomic Properties

Atomic number 27
Atomic radius - Goldschmidt ( nm ) 0.125
Atomic weight ( amu ) 58.9332
Crystal structure Hexagonal close packed
Electronic structure Ar 3d7 4s2
Ionization potential No. eV
1 7.86
2 17.06
3 33.5
4 51.3
5 79.5
6 102
Natural isotope distribution Mass No. %
59 100
Photo-electric work function ( eV ) 5.0
Thermal neutron absorption cross-section ( Barns ) 37.5
Valences shown 2, 3

Electrical Properties

Electrical resistivity @20C ( µOhmcm ) 6.34
Temperature coefficient @0-100C ( K-1 ) 0.0066
Thermal emf against Pt (cold 0C - hot 100C) ( mV ) -1.33

Mechanical Properties

Material condition Soft Hard Polycrystalline
Bulk modulus ( GPa )     181.5
Hardness - Vickers 170 320
Poisson's ratio     0.32
Tensile modulus ( GPa )     211
Tensile strength ( MPa ) 760 1135
Yield strength ( MPa ) 345-485

Physical Properties

Boiling point ( C ) 2870
Density @20C ( g cm-3 ) 8.9
Melting point ( C ) 1495

Thermal Properties

Coefficient of thermal expansion @0-100C ( x10-6 K-1 ) 12.5
Latent heat of evaporation ( J g-1 ) 6490
Latent heat of fusion ( J g-1 ) 263
Specific heat @25C ( J K-1 kg-1 ) 456
Thermal conductivity @0-100C ( W m-1 K-1 ) 100

Buy Cobalt on-line

We stock and supply the following standard forms:
Foil Lump Microfoil Powder Rod Single Crystal Sputtering Target Wire
Foil Lump Microfoil Powder Rod Single Crystal Sputtering Target Wire

Choose a form to search our on-line catalog  

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