The application of galvanized trivalent chromium passivator is more and more extensive. To ensure the stability of product production, what precautions should we take in the use process?
According to the field experience and the characteristics of the product, Bigolly Technology has made the following analysis (taking the galvanized trivalent chromium passivator BZ-212 as an example):
1. During the production process of the passivating agent, the pH value will rise, and nitric acid should be used to adjust it within the process range.
2. The passivating agent can be heated when the temperature is low, but the temperature cannot be higher than the process range.
3. The working fluid should salvage the workpiece or hanger from the tank regularly to avoid the contamination of impurities caused by the workpiece being dissolved for a long time in the tank.
4. The thickness of the workpiece coating is preferably above 5μm.
5. When the iron ion impurity concentration in the working fluid exceeds 50ppm and the zinc ion concentration exceeds 8g/L, the working fluid should be aged and updated.
6. In order to ensure the stable and good working state of the plating solution, the contamination of organic impurities or metal impurities should be avoided as much as possible to affect the passivation effect.
7. After the workpiece is passivated by trivalent chromium, it should be placed for 24-48 hours, and the neutral salt spray test can be carried out after the passivation film is completely aged. The result is relatively accurate.
Therefore, we need to pay attention to the above 7 points in the production process of using galvanized trivalent chromium passivator, which can effectively maintain the stability of the passivation solution and reduce the occurrence of failures.