Some Knowledge Points of Chromium-free Passivator for Aluminum Alloy

Date:

2020-12-17

Since the reform and opening up, with the rapid development of China's metal industry, the high-precision development of metal products is accompanied by the generation of waste water and waste gas noise, in which the discharge of a large number of production waste water has caused serious water pollution, which has become the key testing industry of the Environmental Protection Bureau. The metal industry is paying more and more attention to environmental protection. In order to obtain better anti-corrosion and anti-discoloration performance of metal parts, the anti-corrosion and anti-discoloration ability of the passivated workpiece is greatly improved on the original basis. Chromate passivation process is indispensable in traditional passivation treatment. Due to the use of hexavalent chromium is highly toxic and carcinogenic, harmful to the environment and human health, many countries have strictly restricted

Since the reform and opening up, with the rapid development of China's metal industry, the high-precision development of metal products is accompanied by the generation of waste water and waste gas noise, in which the discharge of a large number of production waste water has caused serious water pollution, which has become the key testing industry of the Environmental Protection Bureau. The metal industry is paying more and more attention to environmental protection. In order to obtain better anti-corrosion and anti-discoloration performance of metal parts, the anti-corrosion and anti-discoloration ability of the passivated workpiece is greatly improved on the original basis. Chromate passivation process is indispensable in traditional passivation treatment. Because the use of hexavalent chromium is highly toxic and carcinogenic, harmful to the environment and human health, many countries have strictly restricted the use of chromate passivation process. Therefore, the emergence of new chromium-free passivator products for aluminum alloys is of great significance to the metal industry and environmental protection.

New chromium-free passivator for aluminum alloyIt also has the anti-corrosion and anti-oxidation capabilities of traditional hexavalent chromium passivator and trivalent chromium passivator. The environmentally friendly chromium-free passivator is mainly composed of zirconium and titanium metal ions, film-forming promoters, stabilizers and pH regulators because it does not contain chromium. Uniform colorless and transparent chemical conversion film can be obtained on the metal surface, with strong corrosion resistance and firm bonding, which can significantly enhance the bonding force between the workpiece and the coating and paint. Compared with traditional hexavalent chromium and trivalent chromium passivators, chromium-free passivators have better environmental performance, can meet the changing requirements of customers, and comply with new environmental regulations.

Therefore, if passivation is required in metal manufacturing, environmental protection must be used.New chromium-free passivator for aluminum alloy. In order to make the aluminum alloy better weather resistance, longer service life, different color appearance, and make the surface sound insulation, heat insulation, fire prevention, anti-skid, anti-corrosion, anti-static and other special properties. In the final stage of the aluminum alloy workpiece production process, the aluminum alloy surface will be coated. However, before coating the aluminum alloy workpiece with electrostatic powder, fluorocarbon paint and thermal insulation coating, the surface of the aluminum alloy workpiece needs to be pretreated. The purpose is to improve the adhesion of the coating and the surface of the underlying substrate through pretreatment, improve the salt spray resistance, moisture and heat resistance, corrosion resistance and water immersion resistance of the coating, and inhibit corrosion under the film.

Chromium-free passivator for aluminum alloy

Matters needing attention in the use of water-based silver paste passivator