The Galvanic Corrosion between Anodized 6061 Aluminum Plate and C1100 Copper Plate Couple

摘要

The galvanic corrosion behavior of anodic AA6061 Al and C1100 Cu couples is investigated. Anodized AA6061-T6 Al plates were produced at different thickness of 1μm, 5μm and 12μm, respectively. The galvanic corrosion current of anodized plate and C1100 copper plate couples was measured using a zero resistance ammeter for 8 hours in two solutions, 3.5wt.% NaCl solution and 1.0 wt.% NaClO solution under temperatures of 25°C, 40°C and 60°C. The results show that the AA6061-T6 aluminum plate without anodizing produced the highest galvanic corrosion current, 1200 μA/cm~2, among the tested specimens under flowing NaClO electrolyte at 60°C. Anodized AA6061-T6 aluminum plates with a 12μm anodized layer produced the lowest galvanic corrosion current, 15 μA/cm~2, in a static 3.5wt.% NaCl electrolyte at 25°C. Severe corrosion attack was observed at the aluminum specimen with thin and non-uniform anodized layer after the galvanic corrosion tests. The anodizing AA6061 Al plate process can effectively reduce the galvanic corrosion of the AA6061 Al and C1100 Cu couples.