Cathodic ProtectionCathodic protection is a method which protects the
metal reliably even at undetected coating holidays.
The protective current supplies electrons to the
structure which is protected. These electrons cover
the electron requirements for the reduction of oxygen
which comes into contact with the metal surface.
Without cathodic protection, these electrons would
have been provided by the decomposition of the
metal. Thus, the potential of the metal surface is
sufficiently reduced to prevent the disassociation of
positive ions from the metal. Where formerly an
anodic reaction took place, the oxygen is reduced
by cathodic reaction. The entire surface of the
structure protected is thus transformed into a safe
cathode, i.e. the metal is " cathodically " protected.