Integrating EIS and wavelet multi-resolution analysis; Part 1: Enhancing monitoring of nonconductive coatings

The goal of this study is to develop a new tool for enhancing monitoring and modeling the quality of nonconductive coatings. The work is divided into two parts. In part 1, the time-frequency domain features using wavelet-based tool and the traditional Electrochemical Impendence Spectroscopy (EIS) measurements are integrated to enhance the monitoring process. In part 2, the modeling process of nonconductive coatings by integrating both tools is described. In this paper, enamel coatings on aluminum substrates are excited with high frequency voltage source of a square wave using three-electrode arrangement. Signals of non-stationary features of the current and voltage response of an enamel coated sample are analyzed using a wavelet-based tool. The rapid result extracted from the wavelet transform is used to detect and monitor any variation in the enamel coating and hence identify the locations where further investigation using EIS should be implemented. The proposed technique is implemented on large sets of laboratory data and shows promising results.