Electrochemical Techniques in Corrosion: Status, Limitations, and Needs

Abstract The corrosion of metals occurs primarily by electrochemical processes involving metal oxidation and simultaneous reduction of some other species. The fundamental understanding of these processes has allowed the development of a number of electrochemical techniques for the study of the corrosion phenomena and assessment of the corrosion rate. In fact, electrochemical techniques are so ingrained in the field that many practitioners think of corrosion rates first in terms of current density rather than thickness or mass loss per unit time. Standard approaches for electrochemical corrosion rate determination are commonly used in the field for on-line monitoring of systems and facilities. Electrochemistry also provides powerful tools for developing fundamental understanding of corrosion phenomena. However, there are some limitations to the abilities of current electrochemical techniques and some needs for the future. This paper describes the status of electrochemical techniques, their limitations, where non-electrochemical methods are required, and future needs in the field.