AC Etching of aluminum capacitor foil

摘要

Aluminum electrolytic capacitor foil is etched in a bath containing 0.5 to 1.8 M hydrochloric acid, 0.2 to 0.5 M aluminum chloride, 0.03 to 0.3 M phosphoric acid, and 0.05 to 0.3 M nitric acid, the molar ratio of said nitric acid to said phosphoric acid being 0.3-5, while subjected to the action of alternating current at 28 DEG to 45 DEG C.