Corrosion resistance of aluminum and aluminum alloy processed products of PVD coating machine: aluminum has high chemical activity. At 20°C, its standard potential is -1.69V, which is easy to interact with oxygen in the air to form a firm and dense oxide film, increasing the standard potential to -0:5V, so aluminum is corrosion-resistant in the atmosphere. The increase of impurities in the PVD coating machine can damage the continuity of the oxide film or form a micro battery, which will reduce its corrosion resistance. The corrosion resistance of aluminum in pure water mainly depends on the water temperature, water quality and the purity of aluminum. When the water temperature is lower than 50℃, with the improvement of water quality and aluminum purity, the corrosion resistance of aluminum will increase; the main type of corrosion is pitting. If the water contains a small amount of active ions (Cu+, Cu-, etc.), the resistance of aluminum will decrease sharply.

       PVD coating machine pure aluminum is higher than aluminum-magnesium alloy; this kind of alloy has a tendency of exfoliation and corrosion under cold deformation, and this tendency increases with the increase of cold deformation. The PVD coating machine is to improve the corrosion resistance of hard aluminum in the ocean and humid atmosphere. It can be artificially protected by covering a layer of pure aluminum, and the purity of the covering aluminum should be greater than 99.5%. For thin plates, the thickness of the aluminum-clad layer shall not be less than 4% of the plate thickness on each side.

       In order to improve the corrosion resistance of the plate, the PVD coating machine can be coated with aluminum on the surface; however, due to the high content of copper in the matrix and easy copper diffusion, its corrosion resistance is still lower than that of 2A12 alloy clad aluminum plates. The corrosion resistance of 2A16 alloy extruded products is not high, and it has a stress corrosion tendency when artificial aging at 160～170℃ for 10～16 h; and its weld and transition zone have a high tendency to intergranular corrosion; anodizing and coating should be used Paint protection.

       The super hard lead of PVD coating machine has higher gold content than hard aluminum alloy, but lower than aluminum-manganese, aluminum-magnesium, aluminum-magnesium-silicon alloys. The PVD coating machine is equipped with super-hard aluminum sheet coated with aluminum; its corrosion resistance is greatly improved. Coating equipment can be used for surface protection for extruded materials and forgings that are not chromium-clad; anodizing or painting can be used. PVD coating equipment super hard aluminum alloy has poor stress corrosion resistance in the quenched natural aging state, but in the quenched artificial aging state, its corrosion resistance increases instead. Recent studies have shown that the use of graded aging technology can reduce its stress corrosion Sensitivity.