Cobalt, like iron, can be magnetised and so is used to make magnets. It is alloyed with aluminium chromium and nickel to make particularly powerful magnets: Permanent Magnet Containing Nickel, Aluminum, Cobalt, And Chromium (1936).
Other alloys of cobalt are used in jet turbines (High-Temperature Cobalt Alloy (1950)), where high-temperature strength is important.
Cobalt metal is sometimes used in electroplating (Electroplating Of Cobalt Or Cobalt Alloy And A Composition For Depositing The Electroplate (1973)), because of its attractive appearance, hardness and resistance to corrosion.
Cobalt salts have been used for centuries to produce brilliant blue colours in paint and enamels (Cobalt containing ceramic decoration paint and its use (1999)), porcelain (Method Of Making Porcelain Ware Decorated With Cobalt 2000, and glass Cobalt glass production (1988)).
Radioactive cobalt-60 is used in radiotherapy (An Apparatus To Deliver Conformal Radiotherapy Using External Beam Cobalt 60 (2015)). Cobalt – 60 is a gamma ray source for Mössbauer spectroscopy, which probes the chemical environment of Mössbauer active nuclei: Mössbauer Gamma Ray Spectrometer (1971).
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All patent information has been obtained from Espacenet (European Patent Office).