New strategy for corrosion protection of Mg alloys under acidic conditions: organic–inorganic composite films

Mg alloy materials frequently encounter exposure to various acidic substances during their application, resulting in significant corrosion challenges. Protecting these alloys from corrosion in acidic environments is notably complex. To enhance the corrosion resistance of Mg alloys under such conditions, researchers have developed an organic-inorganic composite film. This organic layer modifies the properties of the Mg alloy matrix, facilitating the adsorption of metal films onto the surface of the alloy surface. Additionally, this method simplifies the preparation of metal films by eliminating the need for intricate procedures. The findings indicate that the corrosion inhibitor 4-(((1-(4-fluorophenyl)-5-hydroxy-3-methyl-1H-pyrazol-4-yl) methylene) benzoic acid (A1) exhibits remarkable corrosion inhibition properties and can rapidly form a protective film on Mg alloys. Electroless plating techniques were employed to deposit Ni-B/Ni-P metal films onto the A1 precipitation films. Potentiodynamic polarization (PDP) tests demonstrated that the maximum corrosion current density of the Mg alloy with the composite film decreased from 4.63 × 103 μA/cm2 to 12.3 μA/cm2 in a concentrated (0.20 mol/L) hydrochloric acid solution, indicating that the composite films provide effective protection in acidic environments.