4 electroplating methods of aluminum die-casting

1. Phosphating aluminum:

Phosphating is a process of forming a phosphate chemical conversion film by chemical and electrochemical reactions. The phosphate conversion film formed is called a phosphate film. The purpose of phosphating is: to provide protection to the base metal and prevent the metal from being corroded to a certain extent; for primer before painting to improve the adhesion and anti-corrosion ability of the paint film; to reduce friction in the metal cold working process Use for lubrication.

2. Alkaline electrolytic polishing process of aluminum:

The research of alkaline polishing solution system was carried out, and the influence of corrosion inhibitor, viscosity agent, etc. on the polishing effect was compared, and the alkaline solution system with the good polishing effect of zinc-aluminum die casting was successfully obtained, and for the first time, it was obtained that the operating temperature can be reduced. , Additives that prolong the service life of the solution while improving the polishing effect. Polished under this process condition, the surface reflectivity of aluminum after leveling can reach about 87%, and its operating temperature, solution service life, and aluminum loss during polishing are far superior to the reported alkaline DC electrolytic polishing. The surface reflectivity of aluminum can reach 90%, but due to the unstable factors in the experiment, further research is needed.

3. Environmentally friendly chemical polishing of aluminum and aluminum alloy:

Electrolytic polishing refers to the finishing process in which metal products undergo special anodic treatment in a solution of a certain composition to obtain a smooth and bright surface. It can be used to prepare the surface of the product before electroplating, and also be used to finish the surface after planting, and it can also be used as an independent finishing processing method for the metal surface. A smooth and flat surface can be obtained by chemical polishing, which enhances the light reflection ability, heat reflection ability, and corrosion resistance of aluminum, and improves the decorative effect of aluminum products.

4. Electrochemical surface strengthening treatment of aluminum and its alloys：

The process, properties, morphology, composition, and structure of the ceramic-like amorphous composite conversion coating formed by anodic oxidation and deposition of aluminum and its alloys in a neutral system and the film formation process and mechanism of the coating were discussed. Process research results show that, in the Na_2WO_4 neutral mixing system, the concentration of film-forming accelerator is controlled to be 2.5-3.0g/l, the concentration of complexing film agent is 1.5-3.0g/l, and the concentration of Na_2WO_4 is 0.5-0.8g/l, The peak current density is 6-12A/dm~2, and weak agitation can obtain a complete, uniform, and good-gloss gray inorganic non-metallic film. The film has a thickness of 5-10μm, a microhardness of 300-540HV, and excellent corrosion resistance. The neutral system has good adaptability to aluminum alloys and can form a good film on various series of aluminum alloys such as rust-proof aluminum and forged aluminum.