Moderne elektrochemische Methoden der Korrosionsforschung

Abstract

The use of Electrochemical Techniques in Corrosion has gained wide acceptance as a powerful research tool as well as an application aid. The electrochemical nature of corrosion and the fundamental concepts of the Tafel equation and the additivity principle of individual anodic and cathodic reactions are outlined and lead to the general equation of the current density/potential curve. This relation is the basis for most electrochemical methods of determing corrosion rates. Some experimental problems, especially the ohmic potential drop in the electrolyte, and the effect of this error on the results of corrosion rate measurements by AC and DC techniques are discussed.
As examples for the practical application of electrochemical techniques the testing of coatings by AC Impedance measurements and the control of cathodic protection plants by current-interruption are described.