Investigation on Influencing Mechanism of Processing Parameters on Corrosion Resistance and Zinc Content of Anodic Coatings Developed on Magnesium Alloys in Near-Neutral Solutions

In near-neutral solutions, the effects of NH4HF2, H3PO4, phytic acid (IP6), and EDTA-ZnNa2 concentration on corrosion resistance Zn amount micro-arc oxidation (MAO) coatings were revealed by an orthogonal experiment. The influencing order four factors coating is > NH4HF2 IP6 while sequence ranked as H3PO4 IP6. fabricated Zn-containing exhibit excellent resistance, their icorr values are two orders magnitude lower than that WE43 substrate, highest achieves 4.12 wt.%. P F compete to take part in formation, ions enter into anodic diffusion. Coating jointly determined surface characteristics, which will provide important theoretical foundation for fabricating with high resistance.