Effect of MgO Nano - Particles on the Corrosion Resistance of Anodic Oxidation Film on Magnesium Alloy

In order to improve the corrosion resistance of the anodic oxidation film on magnesium alloy，an anodic oxidation film was fabricated on the surface of magnesium alloy by adding MgO nano - particles into the silicate alkaline electrolyte. The effects of MgO nano - particles on the surface morphology, phase composition and thickness of the anodic oxidation film were analyzed by optical microscopy, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), film thickness meter and X - ray diffraction (XRD). Besides, the effect of MgO nano - particles on the corrosion resistance of the anodic oxidation film was analyzed by dropping test and 3.5% NaCl immersion corrosion test. Results showed that adding MgO nano - particles into the electrolyte could reduce the number of micropores in the film and increase its density, thickness and MgO content, thus improving the corrosion resistance of the film.