The corrosion situation of a metal is caused by the electrochemical potential at which it is found in a certain medium. The conceptual solution would be to bring the metal to a potential of immunity or passivity where it does not dissolve in its ions.

​

Cathodic protection of a specific metal consists of lowering the (more negative) potential of the metal to be protected.

​

​

Marine Corrosion

​

​

In the sea, for example, a steel hull made up of 95% iron (Fe) is affected, among other corrosive mechanisms, by the reduction of oxygen in so-called cathodic zones, which provide an attraction for the electrons of the iron, which, when released cause oxidation of the metal, decomposing its structure and altering all its mechanical properties.

​

The corrosion situation of a metal is caused by the electrochemical potential at which it is found in a certain medium. The conceptual solution would be to bring the metal to a potential of immunity or passivity where it does not dissolve in its ions.

​

Cathodic protection of a given metal consists of lowering the (more negative) potential of the metal to be protected below a value defined for each metal, in which corrosion cannot occur thermodynamically. Below this value electrochemical corrosion is eliminated.

​

​

Impressed Current Solution

​

​

If we limit ourselves to applying a negative current to the metal to be protected and the positive pole to the electrolyte (that is, sea water), we will achieve the same effect: lowering the potential of the metal to be protected until we reach the immunity potential of that metal. without the need for sacrificial anodes, only applying the battery current. Therefore, we have protected the metal of the ship's hull by the impressed current system, just as the anti-corrosion equipment does.