Can The Casting Surface Be Anodized? Yes!

Under normal circumstances, die-casting parts will not choose to be anodized, because die-casting parts are denser than aluminum extrusion parts, forgings and stamping parts are very different, and the silicon content is higher, there will be a lot of dust on the surface after anodizing, which will Affect the surface quality of the anodized layer, appearance and performance is not the best choice.

Especially the aluminum-silicon-copper alloy die-cast aluminum ADC10 and ADC12, both of which are Japanese grades. ADC12 is equivalent to the code name YL113 made in China, and the alloy grade is YZAlSi11Cu3, which implements the standard GB/T 15115-2009. The American alloy grade is 384, and the executive standard is: ASTM B 85-03 Standard Specification for Aluminum Alloy Die Casting
In order to develop the ADC12 die-casting anodizing process, if environmental protection laws and regulations permit, HF hydrofluoric acid can be used for pretreatment to remove silicon, and the anodizing treatment can hardly be completed. The resulting black is dull black with a slight yellow color, which is very uncomfortable. . In addition, the abrasion resistance and corrosion resistance of the anode layer of the die-cast part are poor, so anode treatment is not recommended. Moreover, according to the current national environmental protection requirements, it is often difficult to obtain a legal license to use hydrofluoric acid.

Die-cast aluminum (such as ADC6) is an aluminum-magnesium alloy. Anodizing treatment is much easier than aluminum-silicon-copper alloy die-casting, and the appearance effect of surface treatment is much better than ADC12, and its silicon content is usually less than <1.0%.

In order to improve the reliability and quality of the anode layer, such as wear resistance, corrosion resistance, weather resistance, etc., we can perform hard anodizing. The anode pretreatment adopts hydrofluoric acid to remove ash, the anodizing tank adopts monoacid sulfuric acid reagent, the parameter is set to low temperature and high pressure, the film thickness is high film thickness, 100um +, the anodizing tank solution should be dosing maintenance and frequent rebuilding of the bathtub.

In more detail, if a strong acid (such as HF hydrofluoric acid) is used for pretreatment, it may not meet environmental protection requirements now, so it must be used with caution. After all, surface treatment engineers and operators can cause great harm to the body. For samples in the laboratory, labor protection equipment must be worn.

In short, if it is not necessary, do not use die-cast aluminum anodizing process. If the customer must request it, it is recommended to die-cast aluminum-magnesium alloy and then perform hard anodizing.