Electrochemical principles of the corrosion and protection of metals

The types of anode and cathode reactions commonly found in corrosion by aqueous media are described, and the combination of these reactions in corroding and in passivated systems is discussed. The principal ways in which corrosion rates are increased or decreased are classified and discussed, as follows: anodic attack and cathodic protection; anodic passivation or protection and cathodic activation; anodic inhibition and stimulation; cathodic inhibition and stimulation; resistance inhibition. The importance of the use of electrochemical and other theoretical principles in thepracticeof corrosion and protection is emphasised.