It is well known that there are two main methods to avoid and reduce steel corrosion: alloy corrosion protection and electroplating corrosion protection. The alloy anti-corrosion method is mainly to make steel materials into stainless steel containing nickel and chromium. This method is complicated in process and high in production cost; the electroplating anti-corrosion method is to form a metal coating (zinc, aluminum, tin and chromium, etc.) on the surface of the steel. Easy, low cost, has been widely used.
Galvanizing is an electroplating anti-corrosion method for steel parts widely used in the industry. It is widely used in the world, accounting for about 1/3 of the area of all electroplated parts. After the parts are galvanized, in order to improve the corrosion resistance, passivation treatment is usually required. However, the hexavalent chromium in the passivation solution is very harmful to the human body and the environment. At present, the trivalent chromium passivation process developed by the electroplating industry is close to the hexavalent chromium passivation film in terms of corrosion resistance and appearance, and the toxicity of trivalent chromium is roughly 1% of the toxicity of hexavalent chromium. It can greatly reduce the pollution to the environment.
Electro-galvanized use
The purpose of electrogalvanizing is to prevent steel objects from being corroded, improve the corrosion resistance and service life of steel, and at the same time increase the decorative appearance of the product. Steel will be weathered, water or soil corrosion over time. The steel that is corroded every year in China accounts for almost one-tenth of the total amount of steel. Therefore, in order to protect the service life of steel or its parts, electro-galvanizing is generally used to process steel.
Electro-galvanized features
1. Good corrosion resistance, meticulous and uniform combination, not easy to be entered by corrosive gas or liquid.
2. Because the new layer is relatively pure, it is not easy to be corroded in acid or alkali environment. Effectively protect the steel body for a long time.
3. After passivation by chromic acid, it can be used in various colors, which can be selected according to customers' preferences. The galvanizing is elegant and decorative.
4. The zinc coating has good ductility and will not fall off easily during various bending, handling and impact.