LAUSR

Abstract The corrosion behavior and electrochemical migration mechanism of a copper-clad plate (PCB-Cu) in a marine atmospheric environment with industrial pollution were studied in field exposure experiments. The results showed that corrosion was initiated from activity locations with low potential. With extended exposure time, the amount of corrosion products increased and gradually formed a double layer structure. The inner layer corrosion products were mainly Cu2O; the outer layer mainly included CuCO3·Cu(OH)2, Cu(OH)2·CuO·HCl, CuSO4·3Cu(OH)2 and CuSO3·3Cu(OH)2. When a 12 V bias voltage was applied, an anomalous electrochemical migration (ECM) phenomenon was observed: a Cu dendrite was produced near the anode and migrated toward the cathode. Finally, ECM led to the bridge connection of the two metallization stripes and caused a short circuit in the PCB-Cu.