Electrochemical Corrosion

Corrosion resulting from electrochemical interactions between metals and electrolytes is termed electrochemical corrosion. During the process of electrochemical corrosion, electrical currents are generated. Electrochemical corrosion represents an extremely prevalent form of corrosion, encompassing phenomena such as atmospheric corrosion and soil corrosion. This type of corrosion primarily arises from the formation of numerous micro-galvanic cells on the metal surface, caused by the presence of trace impurities (e.g., carbon and other metallic particles) and the formation of a thin electrolyte solution film. When the base metal is more electrochemically active than the impurities, the base metal undergoes dissolution and corrosion. For instance, when the surface of a steel pipe is exposed to moist air, water vapor condenses on the surface and absorbs carbon dioxide from the air, creating micro-galvanic cells and leading to electrochemical corrosion.