Contact person
Karin Törne
Forskare
Contact Karin
PDP for determination of corrosion mechanisms
Linear polarisation (PDP) is an electrochemical technique used to evaluate several critical phenomena associated to electrochemical processes. Corrosion can be studied with the method to determine properties such as corrosion potential, corrosion rate, polarization resistance, passivation, and pitting potential.
Purpose
PDP is a commonly used electrochemical technique to characterize corrosion properties of metallic surfaces with or without protective coating in environments such as water of different salinity (marine environment), soil or battery electrolytes. It is a fast technique often used as an initial measurement of corrosion rate and the stability of protective coatings and films.
Method
Linear polarization is performed by applying a potential with a constant sweep rate (typically 0.16 mV/s) in the range of ± 250 mV vs the open circuit potential. The direction and interval of the sweep can both be adapted for separate study of either anodic or cathodic mechanisms in detail. The changes in current with applied potential (the shape of the polarisation curve) allows for the determination of the corrosion potential, corrosion current, passivation current and breakdown potential of a passivating coating. For more detailed pitting corrosion investigations, Avesta cell measurements are available.
Deliveries
A report with results and analysis presented in text and graphs and calculated parameters such as corrosion rate.
