AZ31和稀土镁合金微弧氧化膜的对比研究  

Comparative Study of Micro-arc Oxidation Coatings on AZ31 and Rare Earth Mg Alloy

作　　者：贾方舟[1] 佟玮 张联英[1] 李吉丹[1] 刘宝军[1] 余剑[1] 

机构地区：[1]首都航天机械公司,北京100076

出　　处：《材料导报》2015年第4期46-49,54,共5页Materials Reports

摘　　要：在相同的工艺参数下制备了AZ31和Mg-10Gd-2Y-0.4Zr稀土镁合金微弧氧化膜层。利用SEM、XRD和EDS对两种陶瓷膜层的组成、微观形貌和元素组成进行了表征;通过电化学测试和盐雾试验评价了两种陶瓷膜层的耐蚀性能;利用显微硬度仪研究了两种陶瓷膜的显微硬度。结果表明:两种陶瓷层的厚度、表面形貌和致密性相似;陶瓷膜由MgO和Mg2SiO4组成,其中MgO为主晶相;与AZ31镁合金陶瓷膜相比,稀土镁合金陶瓷膜中的MgO含量增多,Mg2SiO4含量减少;两种镁合金表面陶瓷化后的耐蚀性和硬度大大提高,AZ31镁合金陶瓷膜耐蚀性优于稀土镁合金陶瓷膜,稀土镁合金陶瓷膜的硬度高于AZ31镁合金陶瓷膜。Ceramic coatings were prepared on AZ31 and rare earth Mg alloy by microarc oxidation with the same process parameters. The phase compositions, morphologies, and element distributions of the coatings were investigated by X-ray diffraction, scanning electron microscopy and energy distribution spectroscopy, respectively. The corrosion resistances of the coated samples were examined by electrochemical method and salt spray test. Meanwhile, the micro-hardnesses of two kinds of ceramic coatings were compared. The results show that the thickness, morphology and compactness of ceramic coating prepared on AZ31 Mg alloy are similar to that of rare earth Mg alloy. The ceramic coatings consist of MgO and Mg2SiO4, in which MgO is the main crystalline. The ceramic coating prepared on rare earth Mg alloy has higher MgO content and less Mg2SiO4 than that of AZ31 Mg alloy. The corrosion resistances and hardnesses for two kinds of Mg alloys with ceramic coatings are improved greatly. The corrosion resistance of AZ31 with ceramic coating is much better than that of rare earth Mg alloy with ceramic coating, and the hardness of ceramic coating prepared on rare earth Mg alloy is superior to that of AZ31 Mg alloy.

关 键 词：稀土镁合金 AZ31镁合金 微弧氧化 盐雾试验 显微硬度 

分 类 号：TG146.2[一般工业技术—材料科学与工程]