Patent ID: 7622030

Claim:
A method for measuring generalized corrosion and localized corrosion rates comprising: (a) placing at least three electrodes in proximity to one another, where i. at least two working electrodes are galvanically coupled via a zero- or low-resistance ammeter used to monitor the potential of the electrodes, and ii. a reference electrode of a material resistant to localized attack used to monitor the potential of the galvanically coupled electrodes; (b) detecting transients in potential data for a localized corrosion event and calculating an area within the transient having units of volts-time; (c) calculating the change in the magnitude of the current data passed during the potential transient for the same time period as (b) and giving it a value with units of current-time (coulombs); (d) dividing the volts-time by the current-time to give the polarization resistance (Rp) as a measure of general corrosion rate; and (e) doubling the charge in (c) to calculate the metal loss caused by the localized corrosion event.