Inhibitive effect of the Ce (III) chloride and nitrate on the corrosion resistance of Zn alloyed sacrificial coatings: Effect of alloying compounds of the sacrificial layer

The corrosion protection of four different zinc-based sacrificial coatings alloyed with Al and Mg were investigated in 0.1 M NaCl with and without 5.10−3 M Ce (III) chloride and nitrate versus immersion time. The effect of Ce (III) chloride and nitrate salts were evaluated by Electrochemical Impedance Spectroscopy (EIS), potentiodynamic polarization measurements, SEM-EDS, and XRD analysis. Cerium salts showed the best effectiveness for HDG, followed by ZnAl, Zn and ZnAlMg coatings. The inhibition efficiency of Ce (III) ions was stable and higher than 82.5% for all types of substrate. Moreover, cerium chloride presented higher protection than cerium nitrate in long immersion time.