Investigation of corrosion behavior of galvanized mild steel by improved Zn acidic bath, containing nano-ZnO particles

Abstract

In this study, nano-ZnO particles were deposited on mild steel sheets from an acidic zinc bath. These particles were synthesized by using an auto combustion technique. The effect of concentration of nano- ZnO particles on the corrosion behavior of depositions was investigated. The results of salt spray tests and electrochemical measurements showed that corrosion resistance is improved by addition of nano-ZnO particles into acidic zinc bath. Based on results, coating contain 0.5g of zinc oxide nano-particles had lowest corrosion rate (1.022mpy) and high corrosion resistance. Scanning electron microscopy (SEM) and X- ray diffraction (XRD) were used for studying the surface morphology and crystal structure of the zinc deposit. SEM observations showed that zinc-oxide nano-particles by absorption of the corrosive agents had action as a barrier against corrosive environment. The study of XRD pattern showed that the adding of nano ZnO was decreased the amount of corrosion products which indicated a higher corrosion resistance than the sample without any nano-particles.