抄録
In the nickel plating bath the electrode potentials of aluminium plates anodized in the phosphoric acid bath, oxalic acid bath and sulphuric acid bath, are measured.
The results are as follows:
i) The electrode potential is enhanced slightly by the anodizing and is always negative disregarding of the electrolyte used in the anodizing.
ii) The highest potential is obtained by using the phosphoric acid bath for anodizing.
iii) The electrode potential of the plate anodized in the phosphoric acid bath is lowered markedly by immersing into the nickel plating bath. This phenomenon is probably originated from the inherent action of the active layer produced by anodizing, which seems to be effective to improve the adhesive property of the electro-deposite.
iv) The potential-current density curve bends near the 20mA/dm2, such bend is most marked in that anodized in the sulphuric acid bath.
