硼-硫酸-草酸电解液降压阳极氧化疏孔膜层制备及表征  

Prepare and Characterization of Aluminum Oxide Films by Under-voltage Process in Boric-sulfuric-oxalic Acids Electrolyte

作　　者：王加余[1] 李澄[1] 尹成勇[1] 李西娟[1] 王艳慧[1] 

机构地区：[1]南京航空航天大学材料科学与技术学院,南京210016

出　　处：《腐蚀科学与防护技术》2014年第2期154-158,共5页Corrosion Science and Protection Technology

摘　　要：使用铝合金在硼．硫酸．草酸电解液中阳极氧化制备有序多孔层。初步探讨了恒流和降压阳极氧化过程膜层生长机理，采用扫描电镜（SEM）观察膜层微观形貌，结合电化学阻抗和动电位极化曲线研究不同阳极化工艺制备膜层试样在3．5％NaCl溶液中的耐蚀行为。结果表明，采用三段变压方式制备的阳极氧化膜表面孔密度降低，孔壁增厚，孔径为10～13am。疏孔膜层的电化学行为表明孔壁及膜层厚度增大能提高试样电荷传递电阻和耐蚀性能。A well ordered porous oxide film on aluminum alloy was prepared by a three-stage pro- cess in electrolyte of boric-sulfuric-oxalic acids. The relevant growth mechanism of oxide film in the processes with modes of galvanostatic and reduced voltage was elaborated. The morphology and microstructure of the oxide films were characterized by scanning electronic microscopy （SEM）. The corrosion performance of the films in 3.5%NaC1 solution was examined by electro- chemical impedance spectroscopy and potentiodynamic polarization curves. The results show that the anodic film exhibits to be regular and dense with pore diameter of 10-13 nm. Moreover, the electrochemical behavior of anodic oxide film could be described as that the impedance and corro- sion resistance was increased with the increasing thickness of the film and the cell wall.

关 键 词：2024铝合金 阳极氧化 降压 耐蚀性 

分 类 号：TG174.44[金属学及工艺—金属表面处理]