03-08-2018, 04:05 AM
Chemical conversion film is the metal and the specific contact with the corrosive liquid, under certain conditions, the chemical reaction occurs in the metal surface to form a layer of good wpc farm fence wholesale adhesion, insoluble film of the product. These layers can either protect the matrix metal from water or other corrosive media, or can improve the adhesion and aging resistance of the organic coating, or can impart other properties to the surface. Since the chemical conversion film is formed because the base metal directly participates in the film forming reaction, the bonding force with the base is much larger than that of the plating layer and the electroless plating layer.
Almost all metals can be converted in selected media to obtain chemical conversion coatings for recycled fence plinth table physical therapy different applications. However, steel, aluminum, zinc, copper, magnesium and their alloys are the most widely used in the industry. The chemical conversion film is not the same as the other metal coating (such as the metal electrodeposition layer), it must have the direct participation of the base metal, and the anion in the medium to produce self-transformation products (MmAn), so it can also be said that the chemical Conversion film ceiling pvc manufacturer kronstadt south africa formation can actually be regarded as a controlled process of metal corrosion.
The chemical conversion film is classified into the oxide film, the phosphate film, the chromate film, and the oxalate film according to the type of the main composition of the film. Aluminum alloys are susceptible to intergranular corrosion and damage in the atmosphere. Currently applied high-strength cast aluminum alloys generally contain elements such as silicon, copper, and magnesium. The addition of these elements increases the corrosion sensitivity of the alloy. Followed by low surface hardness, easy to wear, the appearance of gloss can not be maintained for a long time, so require a higher protective measures. Among them, the chemical conversion long life composite panel Norway coating formed on the surface of the aluminum alloy has the advantages of simple equipment, low cost and investment saving.
Almost all metals can be converted in selected media to obtain chemical conversion coatings for recycled fence plinth table physical therapy different applications. However, steel, aluminum, zinc, copper, magnesium and their alloys are the most widely used in the industry. The chemical conversion film is not the same as the other metal coating (such as the metal electrodeposition layer), it must have the direct participation of the base metal, and the anion in the medium to produce self-transformation products (MmAn), so it can also be said that the chemical Conversion film ceiling pvc manufacturer kronstadt south africa formation can actually be regarded as a controlled process of metal corrosion.
The chemical conversion film is classified into the oxide film, the phosphate film, the chromate film, and the oxalate film according to the type of the main composition of the film. Aluminum alloys are susceptible to intergranular corrosion and damage in the atmosphere. Currently applied high-strength cast aluminum alloys generally contain elements such as silicon, copper, and magnesium. The addition of these elements increases the corrosion sensitivity of the alloy. Followed by low surface hardness, easy to wear, the appearance of gloss can not be maintained for a long time, so require a higher protective measures. Among them, the chemical conversion long life composite panel Norway coating formed on the surface of the aluminum alloy has the advantages of simple equipment, low cost and investment saving.