The aim of the study is to establish a simple methodology for coating evaluation, by using electrochemical impedance spectroscopy (EIS).
Tests were performed in order to study the coating thermal degradation effect on the magnitude of the impedance |Z| at low frequencies. The degree of reversibility of the module of impedance can be a good prediction of simple corrosion resistance samples.
Additionally it was estimated the water uptake by measuring the coating capacitance using the original and modified Brasher-Kingsbury equation and wet glass transition temperature (Tgw) was determined by relationship between log |Z| vs 1/Tabsolute.
It is demostrated by experiments that the changes in the impedance of the system with organic coating allow to determinate the grade of corrosion protection, also the study allows to determinate the reversibility of reactions that occur at interface and determinate water uptake at room temperature and thermal cycling and determinate wet glass vitreous temperature of the coating in a new and faster way them traditional techniques.
