Corrosion resistance of Mg-Mn-Ce magnesium alloy modified by polymer plating

Polymeric nano-film on the surface of Mg-Mn-Ce magnesium alloy was fabricated by polymer plating of 6-dihexylamino-1, 3, 5-triazine-2, 4-dithiol monosodium (DHN) to improve its corrosion resistance. The electrochemical reaction process was analyzed by cyclic voltammetry and two obvious peaks of oxidation reaction were observed. The static contact angle of distilled water on polymer-plated surface can be up to 106.3° while on the blank surface it is 45.8°. Potentiodynamic polarization results show that the polymeric film can increase the corrosion potential from −1.594 V vs SCE for blank to −0.382 V vs SCE. The results of electrochemical impedance spectroscopy indicate that the charge transfer resistances of blank and polymer-plated Mg-Mn-Ce alloy are 485 Ω·cm2 and 2 717 Ω·cm2, respectively. The method of polymer plating can provide a novel approach for fabricating hydrophobic film on Mg-Mn-Ce alloy surface and improving its anti-corrosion property.