Ultrahigh-pressure anode aluminum foil formation method

Abstract

The invention discloses an ultrahigh-pressure anode aluminum foil formation method. The method comprises the steps of preprocessing, forming an oxide film on the surface of the aluminum foil by multi-stage voltage energization, and repeatedly destroying and repairing the oxide film at the constant voltage, wherein the energization voltage is 120 to 1,000V, the formation stage is 4 to 6, and the multi-stage voltage energization is performed in a mixing tank solution which consists of 0.2 to 80 weight percent of boric acid and 0.01 to 0.5 weight percent of ammonium dihydrogen phosphate, and then subsequent voltage energization and repeated destroying and repairing is performed in a mixing solution which consists of 0.2 to 80 weight percent of boric acid and 0.01 to 0.5 weight percent of ammonium pentaborate. In the ultrahigh-pressure anode aluminum foil formation method provided by the invention, ammonium dihydrogen phosphate concentration or ammonium pentaborate concentration in the mixing tank solution is correspondingly reduced as the energization voltage continuously rises, so not only the formation effect is guaranteed, but also the flashing phenomenon in the formation process is avoided and the yield is improved.

Description

technical field [0001] The invention relates to a method for forming an anode aluminum foil, in particular to a method for forming an ultra-high voltage anode aluminum foil. Background technique [0002] With the rapid development of the electronic industry, the application of aluminum electrolytic capacitors is more extensive, and the performance requirements are getting higher and higher. Formed foil for aluminum electrolytic capacitors is the main electronic material for basic components in the electronic information industry, and its quality directly affects the performance of capacitors. [0003] At present, the formed foils widely used in China can be divided into low-voltage foils and medium-high voltage foils according to their formation voltages. Generally, those formed with voltages lower than 170V are called low-voltage foils; those formed with voltages from 180V to 800V are called medium-high voltage foils; The formed one is called ultra-high voltage anodized al...

AI Technical Summary

Problems solved by technology

With the increase of the forming voltage, the aluminum foil is easy to flash fire in the forming bath, causing the aluminum foil to break and affecting the yield

In order to avoid flash fire, it is necessary to reduce the conductivity of the formation bath, that is, to reduce the concentration of ammonium pentaborate, but simply reducing the concentration of ammonium pentaborate will affect the formation effect. Therefore, the formation process of ultra-high voltage aluminum foil is more complicated and difficult to control. Cannot simply adopt the existing medium and high voltage anode aluminum foil formation method