Influence of Additional Alloying Elements on Corrosion Resistance of Hot Dip Galvanised Steels

摘要

The alloying of the zinc with some additional elements in specific quantities could be reliably used in the hot-dip coating process. These elements form specific intermetallic compounds that conferred substantially improved performance to the end-product specially by improving of the corrosion resistance. The paper presents the research that has developed to analyze the influence of aluminum, bismuth and tin like alloying elements added in the zinc on corrosion resistance of galvanized steels. Steel samples were galvanized by the hot-dip method in micro-alloyed zinc baths. The influence of the alloying elements on the formation of the different phases and on the diffusion process is discussed. The corrosion experiments were carried out in a simulated environment of accelerated corrosion conditions. The kinetics and the mechanism of corrosion of the samples were studied in correlation with the effect of alloying elements on nature and characteristics of protective layers.