Abstract
The structure of anodized film on aluminum formed in alkaline bath containing hydrogen peroxide at constant voltages has been studied by electron microscopy. Electron micrographs of the section of anodized film showed that the pores were branched. This structure is much different from the vertical and regular structure proposed by Keller and others. It was found that the pores on the surface increased in size and joint to each other in proportion to anodizing time and that the columns in the wall were widened with a rise in electrolytic voltage. Thickness of the barrier layer was about 12Å/V and not greater than that of the barrier layers formed in ordinary sulfuric acid baths.
