The aluminum plate workpiece is not thoroughly rinsed after alkali washing. If the alkali solution entering the hole during alkali washing is not washed out, the alkali solution will promote the flow out of the cylinder eye after oxidation treatment, causing the oxide film around the hole to be corroded.
There is alive around the perforations of the aluminum sheet workpiece. When the aluminum profile taps the screw hole, it is very sturdy. The operator often lubricates with the coating. If the lye is lacking in the lye during the alkaline washing, it is difficult to remove it.
A problem arises from the excessive accumulation of aluminum ions in the alkali etching solution. A reader calls to inquire about the reason why it is difficult to obtain a conductive oxide film after alkali etching. After eliminating many factors that are difficult to form a conductive oxide film, it is considered whether or not the alkali etching solution is used. There is a problem with high aluminum ion, and the other party said that the alkali etching solution is very thick. However, the rate of alkali etching is not fast.
At that time, the aluminum plate was replaced with an alkali etchant. Because the alkali etchant used for too long, it accumulated too much aluminum ions. The aluminum ions were hard to elute on the surface of the workpiece, which affected the contact between the surface of the aluminum and the conductive oxidizing solution, thus affecting oxidation. Film formation.