Low-Current Cathodic Protection of Metal

A proposed extension of the impressed-current method of cathodic protection of metal against corrosion in wet environments would reduce the current and power needed. The proposal involves (1) the application of a special multilayer coat to the metal part to be protected and (2) the use of a small dc power supply that operates at a precisely chosen low output potential. The effectiveness of protection should justify the costs of power sources and coatings in many situations: metal structures that could be protected by the extended method include ships, automobiles, bridges, metal buildings, radio towers, pipelines, and storage tanks.