In general the Butler -Volmer equation describes the kinetics of a redox reaction close to the formal potential.
Applied to corrosion research the Butler-Volmer equation creates a relation between applied potential E, the measured current I, the corrosion potential Ecorr, corrosion current Icorr and the Tafel slopes for the anodic and cathodic reaction ßanodic and ßcathodic, also known as Tafel constants.
The Butler-Volmer equation is used in corrosion research as a model for a fit to a polarization curve. This way the corrosion current and corrosion potential can be extracted.
A modified version of the Butler-Volmer equation is the Stern-Geary equation.
In this extensive section Polarization Curves are discussed. How to setup your equipment, the choice of parameters as well as the data processing is discussed. This will enable you to record a polarization curve and extract the corrosion rate from it by using PSTrace 5. Furthermore, the polarization curves and Evan’s diagrams for passivation films …