Effects of metal cations on mild steel corrosion in 10 mM Cl− aqueous solution

The influences of metal cations on the corrosion of mild steel in 10 mM Cl− aqueous solutions were investigated by electrochemical techniques and immersion tests. Immersion tests and electrochemical impedance spectroscopy (EIS) results showed that Zn2+ has a significant effect on corrosion inhibition. Surface morphological inspection also showed the smooth surface of specimen immersed in Zn2+ containing solution. Analysis of X-ray photoelectron spectroscopy showed that Zn2+ was incorporated in the oxide films by making a strong bond. It is supposed that Zn2+ forms a very effective shielding film which can inhibit the electrochemical reactions, and consequently lowers the corrosion rate.