An Overview of the Use of EIS Measurements for the Assessment of Patinas and Coatings in the Conservation of Metallic Cultural Heritage

Electrochemical impedance spectroscopy (EIS) is a technique widely used in the field of corrosion science and for coatings evaluation. Its application to the field of cultural heritage started in the early 1990s. Since then, around a hundred references have appeared in conservation and scientific literature addressing different topics such as corrosion processes, field measurements, conservation assessment, and protective coatings evaluation. All of these research results constitute highly valuable information for metal conservators. This paper addresses the state of the art on available setups for EIS measurements in heritage science and presents an overview of the results on different coatings and substrates.