Errors in the electrochemical evaluation of very small corrosion rates—I. polarization resistance method applied to corrosion of steel in concrete

Abstract The Stern and Geary Method of determining R p for measuring corrosion rates is widely used in many systems in spite of its known limitations. The authors consider two of these limitations seldom discussed until now: (a) the time needed for the system to be polarized in order to achieve a reliable response value, and (b) the development of perturbations on the working electrode-electrolyte interphase during the measurements. They apply theoretical considerations to systems of very low corrosion rates, especially the steel-concrete system.