anodizing die cast aluminum is the process of creating an aluminum oxide film on the surface of aluminum or aluminum alloy products by immersing them in an electrolyte solution and applying an electric current. This treatment results in an oxide film that enhances the corrosion resistance, wear resistance, and visual appeal of the aluminum die-casting product.
principle
During the anodic oxidation process, the porous oxide film created on the surface of aluminum has the ability to adsorb dyes, which can be used to color the film layer. The diameter of the anodized pores is typically between 0.01-0.01um, and dyes with a diameter of 0.0015-0.0030um can be isolated into single molecules in water. When the dye is adsorbed onto the surface of the pores and diffuses into them, it accumulates and forms ionic bonds with aluminum oxide, resulting in hydrogen bonds that give color to the film layer. The dyes are fixed in the pores after sealing.
color
The anodizing process can result in a range of colors, including black, silver, and red. The desired color can be selected during the anodizing process to achieve the desired look for industrial aluminum profiles.
Anodic oxidation sealing process of aluminum profile
High-temperature water sealing is a common method for sealing an anodized aluminum oxide film. This method uses the hydration reaction of aluminum oxide film and water to change the amorphous film into a hydrated crystalline film. Another method is inorganic salt sealing, which can improve the fastness of organic coloring dyes. An organic sealing method involves immersing the aluminum oxide film in oil, paint, or another type of coating.
Anodizing coloring process
There are various methods for coloring the anodized film layer, including natural development during the electrolysis process, adding metal salts or other acids to the bath, electrolytic coloring using Ni, Sn, or Ni-Sn mixed salts, and dyeing methods. The porosity of the oxide film is an important consideration when using the dyeing method since the inner wall of the hole must have a certain adsorption capability. The sulfuric acid oxide film is often used since its pores are relatively large, providing a purer dyed film.
In general, the process of anodizing die-cast aluminum involves controlling key parameters such as voltage, current density, bath composition, and concentration to form a porous film on the aluminum surface, then electrodeposit metal or adsorb dye in these pores, and then It's sealed. The resulting corrosion-resistant, wear-resistant, and aesthetically pleasing protective layer enhances the durability and aesthetics of aluminum die-casting products and aluminum alloy die-casting products.