抄録
Current distribution was examined by applying direct current in the vertical type electrolytic cell containing sulfuric acid with an anode of a long aluminum sheet. It was carried out by the measurement of thickness of anodic oxide coating and color difference in dyed specimens and by the observation of burnings of anode.
Current distribution was more uniform when the concentration of acid was higher, the concentration of aluminum was lower, anodizing temperature was higher, anode current density was lower, and circulation velocity of electrolyte was higher. When the current density was extremely bad in uniformity, current passed through a certain point, at which burnings were produced. Shape and size of burnings would depend upon convection of heat generated on the anode. The two step raise of the current at the early stage of anodizing was effective for preventing the production of burnings. Moreover, studies were also made on the effects of arrangements of the electrodes.
