How to process galvanized square tube electroplating?

Galvanized square tube processing is the use of the principle of electrolysis, through the electrolytic process of metal ions on the surface of the product deposited a layer of metal or alloy layer, in order to change the physical and chemical properties of the product surface, and finally make the galvanized sheet has wear resistance, decorative and impact resistance, etc., in addition, it can be coated with a specific coating according to the special requirements of specific products, such as light energy and electromagnetic coating, etc. This can fully expand the application field of galvanized square pipe.

The electroplating process of galvanized square and rectangular tube mainly includes pre-treatment, electroplating and post-plating treatment. The quality of the coating depends on the plating process of the material, and the plating process is affected by many factors. The six main factors are summarized below:

1. Zinc content: The higher the zinc purity of the zinc block, the narrower the brightness range, the easier it is to obtain a thicker coating, and the iron content in the coating will be lower. When the purity of the zinc block is too low, its light range will be wider, and it will take longer to reach the specified zinc layer thickness, which will result in a higher iron content of the galvanized layer.

2. Sodium hydroxide: Sodium hydroxide has a double effect on the reaction. When its content is too high, it is easy to burn when running at high temperature. When its content is too low, the dispersion of the solution is poor, which will reduce the quality of the zinc layer.

3. Iron content: When the iron content is too high, there will be more iron in the coating, which will lead to insufficient passivation film brightness of the product. The iron content is too low and the iron content in the galvanized layer is low, which will reduce the corrosion resistance of the automobile plate and cause the surface of the automobile plate to be olive.

4. Brightener: The most used brightener is ZF-100A and ZF-100B. If the concentration of the former is too high, the brittleness of the coating will be enhanced, while if the concentration is too low, the coating in the low current region will be sparse, resulting in poor passivation effect. The average phenomenon.

5. Temperature: During the plating process, the temperature is too high, which will reduce the dispersion of the solution, increase the iron content in the coating, and the passivation is not uniform. When the reaction temperature is too low, it is easy to burn into a high current density region, the coating is brittle and the deposition rate is slow.

6. Cathode moving speed: During the plating process, the cathode must be in a moving state. If the moving speed is too fast, the coating in areas of high current density will become rough during the plating process. If the moving speed is too slow, air flow may be generated, resulting in uneven coating of the material.

Galvanized square rectangular tube with zinc as electroplating metal, electrolyzed Zn2+ solution, and then deposited on the surface of galvanized square rectangular tube to form a uniform and dense zinc metal layer. Compared with other metals, zinc is an amphoteric metal easily soluble in acid and base, and it is easy to electrolyze metal ions in solution. The above aspects should be paid attention to in the processing of galvanized square rectangular pipe in order to produce high-quality qualified galvanized square rectangular pipe products.