A critical review on electrochemical noise measurement as a tool for evaluation of organic coatings

摘要

Since first introduced to the field of organic coatings about three decades ago, electrochemical noise measurement (ENM) has proved to be a reliable method for examining protective properties of coatings in the laboratory situation. Use has also been made of the technique in field situations. Simplicity of measuring equipment and versatility of data analysis makes ENM an ideal technique for acquiring electrochemical information about the corrosion behaviour of a painted metal and the protection afforded by the organic coating relatively quickly. Special care must be taken in choosing data acquisition parameters, reference electrodes and symmetry of electrodes in order to achieve reproducible measurements. Several areas have been discussed in this review including the methods of data analysis, alternative electrodes configurations for on-site measurements and novel applications of the technique. Although there is still room for some development work, the view of the authors is that this technique has "come of age" in relation to its applicability to assessment of the level of protection afforded by organically coated metal.