Estimation of the microstructure of anodic porous oxide films on aluminum by the pore-filling method I. Analysis of film structure formed by two-step anodizing
Pore‐filling法による多孔質Alアノード酸化皮膜の微細構造の推定 I 二段化成皮膜の構造解析

Hideaki TAKAHASHI, Hitoshi KUMAGAI, Masaichi NAGAYAMA
1985 Journal of the Metal Finishing Society of Japan  
Double layered porous oxide films were formed on aluminum by two step anodizing at an initial current density (i1) in a H2SO4 solution (S-layer) and again at a second current density (i2) in a H2C2O4 solution (O-layer). The anodized specimens were re-anodized in a neutral borate solution at constant current density to follow the change in anode potential (E) with time (t). The geometrical structre of the double layered films was estimated by analysing the E-t curves (pore-filling method). It
more » ... ling method). It was found that the structure of the O-layer was dependent on i2, but independent of the structure of the S-layer formed at i1. Pore-widening in the S-layer was observed to take place by chemical dissolution during the formation of the O-layer. (1) Fig. 1 Schematic model of (a) the •gpore-filling•h of porous anodic oxide films and (b) the time-variation in the anode potential during galvanostatic anodizing in a neutral borate solution.
doi:10.4139/sfj1950.36.478 fatcat:4yfr2wwxxjde5jpc5xdchbgeae