Corrosion is the reaction of a metallic material with its environment. In all electrolytes, as for example, in the ground, in river or sea water Metal atoms go into solution as electrically charged ions during the corrosion reaction. This process produces a more or less loss of metal surfaces. The simultaneous movement of charges in electrolyte and electrons in metal, causes a flow of current in the metalelectrolyte circuit.


Anodec reaction Fe→Fe++ +2e-