First, when the oxide film is powdered and dusty, we should try to erase it first. To close the process caused by the sealing ash and electric ash to sweep away.
Secondly, the origin of oxidizing powder ash is analyzed one by one.
Generally, the film layer is caused by the following points:
1. The oxidation tank temperature is too high;
2. Sulfuric acid concentration is too low;
3. The content of aluminum ion exceeds 18g/L. (The reason for the rapid increase of aluminum ion content is also mainly caused by the high temperature of the oxidation tank, and then the oxidation tank dropped parts are not salvageable in time)
Oxidation tank temperature is too high, to determine the cold motor equipment is not large enough? If the usual cooling capacity can also be considered, it is necessary to consider the size of the cold water circulation, whether the circulation pump blockage formed by the temperature is too high, one by one cleaning.
Sulfuric acid content should be measured and made up regularly according to the consumption of sulfuric acid taken out of the oxidation tank every day. Keep the time within the process range (180-220g/L is the best).
The temperature of the electrolyte has a great influence on the wear resistance of the oxide film. Generally speaking, if the temperature drops, the wear resistance of the anodic oxide film of aluminum and aluminum alloy increases, which is caused by the decrease in the dissolution rate of the electrolyte for the film, in order to obtain higher hardness of the oxide film. We should control the temperature within ±2℃ for hard anodic oxidation treatment as well.
