A new technique for online visualization of the electrode surface under electrochemical corrosion processes

A new method for the online visualization of corrosion processes has been d eveloped. It relates two techniques, electrochemical studies (potentiodynam ic, potentiostatic, chronoamperometric etc.) and image processing. The main advantage of this method is that it is possible to relate the morphologica l changes of the electrode surfaces to the electrochemical signal measured without disturbing the electrochemical system. The online visualization tec hnique is based on a horizontal electrochemical cell. The cell allows obser vation of the surface of the electrodes in a horizontal position by means o f a triocular microscope-stereoscope assembled to an image acquisition syst em. The methodology was applied to the study and understanding of the surfa ce changes of a copper and an AISI 316L electrode, respectively, when their potentiodynamic curves were taken in a lithium bromide solution. The corro ded area of an AISI 316L electrode was determined by image processing in or der to calculate the local current density in a potentiostatic test. The vi sualization method proposed can be used to gain a better understanding of e lectrochemical corrosion processes.