Microstructure and Corrosion Resistance of Two-Dimensional TiO2/MoS2 Hydrophobic Coating on AZ31B Magnesium Alloy

Abstract

The corrosion resistance of magnesium alloys can be effectively improved by surface treatment. In this study, a hydrophobic two-dimensional (2D) TiO2/MoS2 nanocomposite coating was fabricated on AZ31B magnesium alloy by an electrophoretic deposition method. The corrosion resistance of the coating was evaluated using potentiodynamic polarization and electrochemical impedance spectroscopy analyses. After being modified by a silane coupling agent (KH570), the TiO2/MoS2 coating changed from hydrophilic to hydrophobic, and the static water contact angle increased to 131.53°. The corrosion experiment results indicated that the hydrophobic 2D TiO2/MoS2 coating had excellent anticorrosion performance (corrosion potential: Ecorr = −0.85 VAg/AgCl, and corrosion current density: Icorr = 6.73 × 10−8 A·cm−2). TiO2/MoS2 films have promising applications in magnesium alloy corrosion protection.