The cause analysis and solution for can't be dyed of anodizing on the proximal edge of the lower end of machined aluminum products.

The cause analysis and solution for can't be dyed of anodizing on the proximal edge of the lower end of machined aluminum products.

The reason is that no oxide film is formed on the part where the machined aluminum product is not dyed. If the neutralization and water washing are not sufficient, the alkaline free water of the machined aluminum product surface will flow down slowly during the drying process, and the water droplets are integrated at the end of the air and will not disappear for a long time, acid or alkaline substances in water droplets react directly with machined aluminum parts, especially the surrounding areas of the location of oxygen absorption of the water drops, it was not broken down when anodizing, the formation of artificial oxide film during the anodizing process is impeded.

Resolvent:

First, we must conscientiously carry out the pretreatment process, and never afraid of the trouble and simplify the technological process.

Second, for the machined aluminum parts with blind holes, the residual solution in the blind hole should be thrown away in every process of pretreatment.

Third, after pretreatment, it can not be dried with compressed air or baked in oven.

Fourth, during the natural air drying process, we should always use clean towels to absorb water droplets to prevent the acid and alkali substances in the beads from reacting with the place.

Fifth, when natural air drying, we should choose a better environment to prevent acid, alkali, lampblack and erosion.