The limits of the Pourbaix diagram in the interpretation of the kinetics of corrosion and cathodic protection of underground pipelines

This article deals with the basics of corrosion and corrosion protection, with the focus on equilibrium thermodynamics. Particular attention is paid to the easy-to-understand creation of Pourbaix diagrams, their uses, and limitations of this tool. In addition, the basics of electrochemical kinetics are dealt with to provide an overview of the possibilities and the interaction of both methods. Finally, it is argued that the globally recognized and practice-proven protection potential criteria remain valid.