Cathodic protection

Cathodic protection is a system of preventing corrosion by forcing all surfaces of a structure (e.g. hull) to be cathodes by providing external anodes. It can be achieved by superimposing on the hull an impressed current provided by a remote power source through a small number of inert anodes (impressed current cathodic protection). Also accomplished by fitting aluminium, magnesium or zinc anodes in tanks or underwater portion of a ship, which waste away by galvanic action (sacrificial anode cathodic protection).

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