Comparison of the corrosion protection of normal and galvanized steel coated by cathodic electrocoatings via EIS test method

Cathodic electrocoatings were applied on phosphated normal and galvanized steel substrates with average dry film thickness of 20 μm. To evaluate of anti-corrosion aspects, electrochemical impedance spectroscopy (EIS) was carried out on the electrocoated samples. The results showed that by increasing the curing temperature, the protective properties of electrocoated galvanized steel are improved compared to the electrocoated normal steel (the magnitude of pore resistance is about 2 orders more), but at low curing temperatures the protective properties of electrocoated normal steel are better than galvanized steel (the magnitude of pore resistance is about 2 orders more).

کلیدواژه ها:

Corrosion ، Cathodic electrocoating ، Galvanized steel ، EIS