Abstract
Abstract When artificial defects are produced on organic coatings applied to metals it is common to observe a separation of anodic and cathodic defects. An investigation is presented in which real defects are imitated by two disk electrodes of the same metal, embedded in insulating matrix and electrically connected. A variety of measurements was performed to characterise the corrosion of this twin electrodes set-up: SVET, micro-distributions of pH and dissolved O 2 , polarisation curves, galvanic current and video monitoring. The tendency for anodic and cathodic processes to proceed in separated electrodes was observed. It became clear that a strong increase in local pH on the cathode renders it passive to metal oxidation while the other electrode corrodes. It is possible to explain the maintenance of the separation in time but what triggers the separation at the beginning of immersion remains unidentified.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
