Electrochemical impedance studies of corrosion protected surfaces covered by epoxy polyamide coating systems

摘要: Abstract Electrochemical impedance spectroscopy (EIS) was used to study the corrosion behavior of different types commercial quality epoxy polyamide dry coatings on mild steel, with thickness between 150 and 250 μm, which were previously weather accelerated in a wet chamber. The following data established basis curves corresponding equivalent circuits: coating capacity that relates dimension, pore resistance represents conductive paths through pores, Warburg coefficients, are measure ion diffusion coating. EIS compared criterion European standard, samples classified their quality, also receiving final ranking by summing-up all individual rankings. Suggestions have been made, namely use anticorrosive active pigments is obsolete, when exceeds 200 μm.