压铸镁合金阳极氧化膜的研究

Study on Anodic Oxidation Film of Die-casting Magnesium Alloy

研究了压铸镁合金AZ91的阳极氧化膜的工艺及其耐蚀性,探讨了镁合金表面阳极氧化膜的组织、相、成分及其耐蚀性。研究结果显示,压铸镁合金AZ91阳极氧化膜表面系氧化物的聚集,阳极氧化膜在3.5%NaCl中的极化曲线与AZ91压铸镁合金的极化曲线对比,阳极氧化膜的极化曲线有明显的钝化区,但在极化区只呈锯齿状变化,耐蚀性较好。

Anodic oxidation technology of die-casting magnesium alloy AZ91 and corrosion resistance of the anodizing film were studied. Structure, composition and corrosion resistance of the anodic oxidation film on the magnesium alloy surface were discussed. The research results show that anodic oxidation film surface of the die-casting magnesium alloy AZ91 is congregated by oxides. As compared with the pure AZ91, the anodic polarization curve of the anodic oxidation film of AZ91 in 3.5% NaCl solution exhibits an obvious passivation region. This suggests that the anodic oxidation film on die-casting magnesium alloy AZ91 has better corrosion resistance.