复合稀土铝阳极氧化膜的耐蚀性研究  

Corrosion Resistance of Rare Earth Modified Anodized Films on High Purity Aluminum

作　　者：李启征[1] 左禹[1] 熊金平[1] 赵旭辉[1] 

机构地区：[1]北京化工大学材料科学与工程学院,北京100029

出　　处：《中国稀土学报》2009年第5期657-663,共7页Journal of the Chinese Society of Rare Earths

基　　金：国家自然科学基金(50571006)资助项目

摘　　要：用金属氧化物前驱体法,在前处理阶段添加稀土再进行阳极氧化,获得了Nd和Ce改性的铝阳极氧化膜。稀土含量在靠近氧化膜/基体界面处达到0.9%左右,由内向外逐渐降低,氧化膜外表面处的含量约为0.5%。稀土前处理后制备得到的阳极氧化膜耐蚀性能比普通硫酸阳极氧化膜有明显提高,其中Ce改性的氧化膜作用尤为明显;经过NaC l溶液浸泡15 d以后,经稀土改性的阳极氧化膜仍然保持良好的耐腐蚀性。稀土引入后,阳极氧化膜的孔径变小,膜更加致密,显微硬度提高。XPS测试表明氧化膜中的稀土Ce以CeO2和Ce2O3形式存在,而Nd以Nd2O3形式存在。阻抗测试表明氧化膜阻挡层的阻抗值增大,说明稀土除了改变氧化膜生长机制外,也可能通过掺杂作用改变氧化膜结构。By the precursor method of layered double hydroxide, Ce and Nd were introduced on the high purity aluminum surface, which was then anodized, and the rare earth modified complex anodic oxide films were got. The content of rare earth elements reduced gradually from the inside out, about 0.9% in the oxide film/substrate interface and about 0.5% on the surface of oxide film. The corrosion resistance of rare earth modified anodized films were markedly improved in neutral NaCl solution and immersion test, and the Ce modified oxide film was particularly evident. After introducing of rare earth elements, the porous of ano- dized film were smaller, and the micro-hardness was increased. The XPS test showed that Ce was in the form of CeO2 and Ce2O3 in modified anodized films, and Nd was in the form of Nd2O3. The electrical impedance spectroscopy （ EIS ） measurements showed that the value of impedance of the oxide film barrier increased. The rare earth elements changed the growth mechanism of oxide film, but also structure of the oxide film by mixed might change the effect.

关 键 词：铝 阳极氧化 氧化物前驱体法 耐蚀性 稀土 

分 类 号：TG146.2[一般工业技术—材料科学与工程]