硼-硫酸-草酸电解液降压阳极氧化疏孔膜层制备及表征

A well ordered porous oxide film on aluminum alloy was prepared by a three-stage process 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% NaCl solution was examined by electrochemical 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 corrosion resistance was increased with the increasing thickness of the film and the cell wall.