Short-term corrosion behavior of galvanized coatings in natural waters of the Greek territory

The corrosion behavior of hot-dip galvanized steel immersed in domestic and seawater was investigated after an exposure period up to 10 days. The examination of the coatings was accomplished with optical microscopy, scanning electron microscopy and X-ray diffraction. From this investigation it was deduced that the corrosion process in domestic water is slow and mainly proceeds through pitting corrosion, while the corrosion phenomena in seawater are more intense. The main mechanisms in this environment are pitting and intergranular corrosion. In both waters the Cl– and the O2– ions diffuse in the coating up to the Fe/Zn interface. Especially in seawater the Cl– ions seem to be very aggressive.