New experimental arrangement for the acquisition of electrochemical noise data from high resistance organic anti-corrosive coatings

This work investigates the single substrate (SS) technique for obtaining potential and current noise data for electrochemical noise measurement (ENM) analysis. The technique uses a single substrate element, and has shown promise as a useful application for use in the field. The traditional two working electrode approach of obtaining data is hindered by the fact that two electrically isolated substrate elements are required to act as working electrodes. The SS technique addresses this problem, theoretically enabling ENM to be made on any structure using just one electrical connection to the metallic substrate. Results are presented for anti-corrosive organic coating systems intended for marine applications that have very high resistance values (> 1 × 109ohm-cm2). In addition data obtained from previous work that looked at a single coat anti-corrosive primer after a short period of time in immersion and giving Rn values of around 1 × 108ohm-cm2 are presented. Good agreement is seen between values of Rn obtained from the traditional two working electrode method and those obtained from the single substrate technique over both ranges of resistance