抄録
A new type of electrochemical random signal analysis technique was applied to galvanic corrosion of anodic oxide films formed on 6061-T6 aluminum alloy in NaCl containing 0.5 kmol⁄m3 H3BO4 ⁄ 0.05 kmol⁄m3 Na2B4O7 solutions. The effect of the anodic oxide film structure on the galvanic corrosion resistance was also examined. During incubation (before localized corrosion started), both current and potential change slightly from the initial value. The incubation period of porous type anodic oxide specimens is longer than that of barrier type anodic oxide specimens. During localized corrosion, the current and potential changing with fluctuations, and the potential and the current fluctuations show good correlation. The slope of the PSD of both potential spectra of anodized specimens is about minus one ( -1 ), after the localized corrosion has started. This technique allows observation of electrochemical impedance changes during localized corrosion.