Effect of acid concentration and current density on DC etching of aluminum electrolytic capacitor foil

This work studies the effects of acid concentration and current density on etching morphology, microstructure and static capacity of the aluminum foils used in high-voltage electrolytic capacitors. The behavior associated with electrochemical etching was investigated with a potentiostat. The aluminum etching type of DC etching is greatly influenced by the etching potential. The static capacity increased to 0.65 uF/cm² with 540 V forming voltage by optimization of the etching parameters used in this work.