Technical note Novel configurations for electrochemical noise measurements

Abstract

Two novel methods for electrochemical noise measurement have been investigated. A new configuration which is electrically equivalent to the traditional bridge method has been used to eliminate the requirement for two isolated specimens and a salt bridge. The technique shows promise for development as a field application both for continuous monitoring and testing. In the laboratory the technique produced less scatter than the traditional method over a range of resistance from <3 × 10² to > 1 × 10¹⁰ Ω cm⁻². A laboratory technique has also been investigated for making electrochemical noise measurements on detached coatings. It has the advantage of the working electrodes (the metal substrates) being replaced where necessary with saturated calomel electrodes. This has been shown to be a useful tool for assessing the pelformance of coatings and results correlate well with attached and dc data. Water borne coatings and solvent based coatings were examined with both techniques.