Kobaltem

Kobaltem is a metallurgical surface finishing process in which a layer of cobalt or a cobalt-containing alloy is deposited onto a substrate. The term is used in Dutch and other European languages and generally corresponds to cobalt electroplating or cobalt deposition. The process is most commonly achieved by electroplating, where the substrate acts as a cathode in an electrolytic bath containing cobalt salts such as cobalt sulfate or cobalt chloride, often with complexing agents. Electroless cobalt deposition is an alternative that deposits cobalt alloys through autocatalytic chemical reduction, typically producing alloys with phosphorus or boron. Another route is physical vapour deposition, such as sputtering, for high-purity cobalt coatings.

Coating thickness is typically a few micrometers up to tens of micrometers, depending on the intended use. Proper surface preparation, including degreasing, cleaning, and surface activation, is essential for good adhesion. Cobalt coatings can improve hardness, wear resistance, and corrosion resistance, and may impart favorable magnetic properties. They are applied to components such as cutting tools, gears, bearings, valves, and certain electronic or magnetic parts where increased surface performance is desired.

Limitations include costs and potential brittleness if the coating is thin or stressed. The quality of adhesion depends on substrate material and coating method. Safety concerns require handling of cobalt compounds with adequate ventilation, containment, and waste treatment in line with regulatory requirements.

Related topics include electroplating, cobalt, and surface finishing.