ZL系列铸铝合金的微弧氧化

Microarc oxidation of ZL cast aluminum alloys

对含硅量为 8 %～ 12 %的ZL系列铸铝合金的微弧氧化工艺条件、膜层结构以及成膜过程进行了研究。结果表明 :采用不对称交变电压和在以硅酸钠为主要成分的复合电解液体系中 ,铸铝合金表面可获得一层性能优异的微弧氧化膜层。电子能谱 (EDS)和X射线衍射 (XRD)分析结果表明微弧氧化膜主要由Al,Si和O元素组成 ,膜的相结构主要为 η Al2 O3 ,α Al2 O3 和SiO2 ,并含有γ Al2 O3 和Mg ,W ,Cu等元素的氧化物。扫描电镜 (SEM)分析表明微弧氧化膜由致密层 (内层 )和疏松层 (外层 )构成 ,疏松层表面存在许多气孔 ,而致密层完整光滑 。

The microarc oxidation (MAO) process and the corresponding film structure and properties of ZL cast aluminum alloys containing 8%～12% of Si were investigated. Using non-symmetric AC potential source, a MAO film with good properties can be obtained on the surface of ZL alloys in mixed electrolyte solutions containing sodium silicate (Na 2SiO 3). According to the results of energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD), the elements of MAO film are Al, Si and O, and the corresponding phase structure are η-Al 2O 3, α-Al 2O 3 and SiO 2. γ-Al 2O 3 and oxides of Mg, W and Cu are also observed. Scan electron microscopy(SEM) results show that MAO film can be divided into two layers: compact(inner) and porous (outer) layers. MAO films have high hardness and excellent anti-wearing and anti-corrosion properties.