Die cast aluminum always presents many problems when anodizing, such as the impure surface oxide film, which directly turns black and gray after anodizing. What is the reason? Is die cast aluminum suitable for anodizing after all?

First of all, anodizing requires that the aluminum surface is free of impurities and the aluminum material is relatively pure, because it is necessary to ensure that the anodized film is uniform and flat. The existence of too many impurities and other components will inevitably affect the thickness of the film formed during anodic oxidation, and even directly affect whether the film is formed or not. Most importantly, other metal elements may directly change the color of the anodized film when it is formed, which will directly sentence the death penalty for the dyeing after anodizing.

Cast aluminum alloy and die-casting parts generally contain high silicon content. Even if ht412 special ash remover for die-casting aluminum is used, the anodic oxide film may be dark and it is difficult to obtain a colorless and transparent oxide film. With the addition of silicon content, the color of anodic oxide film changes from light gray to dark gray to black gray. Therefore, cast aluminum alloy is not suitable for traditional anodizing.

But die cast aluminum also has anodizing solutions. Die casting can finish the structure, edges and corners, oxidation quality that forging parts and turning parts / CNC parts are difficult to achieve. It is very important to focus on the quality of die casting. A slight change and detailed process support control determine the quality of anode.

For manufacturers engaged in die-casting oxidation, it is necessary to scientifically control the flow channel skills, die-casting process and post-processing methods of the die. With this series of strict control processes, the smooth production of oxidation quality can be guaranteed. This includes: mold runner, gate planning, mold temperature control; For the application of materials, ht412 special ash remover for die-casting aluminum can generally be used to remove the black ash on the surface and avoid polluting elements; Die casting process control to reduce water marks and black watermarks; Blank pre-processing; Selection of anode surface treatment plant, etc.

Die cast aluminum can be anodized, but compared with its aluminum, the requirements are higher, and the labor and cost are slightly higher. The control of various parameters and processes should be slightly strict. In fact, there are other processes that can replace anodizing. If it is not necessary, other processes can be properly considered.