A customer has reported that during the production process of using galvanized blue white passivation agent, the stability of the passivation solution is poor, and the workpiece is prone to yellowing and fogging after passivation. Additionally, the aging rate of the passivation solution is fast, and the dosage of the passivation agent is large. What methods can we use to improve the stability of the passivation solution and delay its aging rate?
Based on on-site experience and the characteristics of BZ-212 passivation agent for zinc plating, Bigley Technology has analyzed the methods to effectively improve the stability of passivation solution and delay the aging rate of passivation solution during the production process:
1. Strictly control the concentration, temperature, and pH value of the passivation working solution within the process range. For example, when using BZ-212, the concentration of the passivation solution is 25-60ml/L, the temperature is 20-35 ℃, and the pH value is within the range of 1.8-3.0. However, large deviations or fluctuations in these parameters can affect the stability performance of the passivation solution.
2. The nitric acid used in production should be analytically pure, and cheap and inferior nitric acid should not be used to avoid introducing more impurities that may affect the performance of the passivation solution.
3. During the production process, attention should be paid to replacing the polished water and the cleaning water before passivation in a timely manner to ensure that the surface of the workpiece is thoroughly washed after the polished water, and to avoid bringing the polished water into the passivation solution.
4. As production progresses, the content of iron and zinc impurities in the passivation solution continues to accumulate. When the iron and zinc impurities reach a certain value, it will cause the appearance of the passivation film to become blurred and significantly reduce the corrosion resistance of the coating. Therefore, Bigley suggests that customers should promptly remove the workpiece from the groove during the production process, and regularly age the passivation solution. That is, discharge 10% -20% of the passivation solution from the bottom every two days, and then add passivation agent. This can effectively improve the temperature performance of the passivation solution and extend its service life.
Therefore, we need to pay attention to the above four points in the production process of using galvanized blue white passivation agent, effectively improving the stability of the passivation solution, delaying the aging rate of the passivation solution, and thus saving production costs. If you are interested in galvanized blue white passivation agent, please contact Bigley customer service to obtain free samples and detailed technical information!
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