AZ91D镁合金磁控溅射镀铝膜及其化学转化后的耐蚀性  

Magnetron sputtered aluminum film on AZ91D magnesium alloy and its corrosion resistance after chemical conversion treatment

作　　者：韦春贝[1] 代明江[1] 高阳[1] 侯惠君[1] 肖晓玲[1] 

机构地区：[1]广东省工业技术研究院(广州有色金属研究院)新材料研究所,广东广州510651

出　　处：《电镀与涂饰》2012年第4期30-33,共4页Electroplating & Finishing

基　　金：广东省自然科学基金项目(9151065101000002)

摘　　要：采用磁控溅射镀铝与化学转化复合处理的方法对AZ91D镁合金表面进行处理,制得复合处理膜层,并与单纯磁控溅射镀铝膜层的耐蚀性进行了比较。结果表明,磁控溅射所得铝膜层结构致密,铝膜层与镁合金基体界面形成混合过渡层。沉积铝膜后再进行阿洛丁化学转化所得膜层表面存在裂纹,化学转化膜与铝膜之间结合良好。磁控溅射铝膜层使镁合金的腐蚀速率加快。镀铝与化学转化复合处理所得膜层的腐蚀电流密度比镁合金基体低1个数量级以上,表明镀铝与化学转化复合处理可明显提高镁合金的耐蚀性。中性盐雾试验4h后,铝膜表面腐蚀严重;而复合处理膜层在试验24h后表面只出现少量的腐蚀,48h后只有5%的面积被腐蚀。A composite film was prepared on AZ91D magnesium alloy surface via magnetron sputtering followed by chemical conversion. The corrosion resistance of the composite film and the magnetron sputtered aluminum film was compared. The results showed that the magnetron sputtered aluminum film is compact and there is a mixed transition layer formed at the interface between aluminum film and magnesium substrate. The surface of the magnetron sputtered aluminum film has cracks after chemical conversion treatment with Alodine and the conversion coating is well adhered to the aluminum film. The magnetron sputtered aluminum film accelerates the corrosion rate of magnesium substrate. The corrosion current density of the composite film is at least one order of magnitude lower than that of magnesium substrate, indicating that the composite treatment of magnetron aluminum sputtering and chemical conversion improves the corrosion resistance of magnesiumalloy. The magnetron sputtered aluminum film is corroded severely after 4-hour neutral salt spray （NSS） test. But for the composite treated film, slight corrosion occurs on its surface after 24-hour NSS test and only 5% area is corroded after 48-hour NSS test.

关 键 词：镁合金 铝 磁控溅射 化学转化 复合处理 耐蚀性 

分 类 号：TG174.44[金属学及工艺—金属表面处理] TQ153.6[金属学及工艺—金属学]