Common problem

4 reasons why the color of the workpiece is very slow during the use of galvanized trivalent chromium black passivator

2022-05-26

    In the production process of using galvanized trivalent chromium black passivator, sometimes the coloring of galvanized workpieces is slow during passivation, which affects the efficiency of production.What is the reason for this phenomenon?

     Bigolly Technology made an analysis based on the field experience and the characteristics of the product's galvanized trivalent chromium black passivator BZ-216,There are four main reasons:


    1. The pH of the passivation solution is too high.The pH value is high, the coloring speed is slow, the passivation film is foggy and not clear, and the pH value of the passivation solution should be adjusted in time to 1.8~2.2.

    2. The temperature of the passivation solution is too low.The passivation temperature should be controlled at 25~35 ℃, the temperature is low, the film forming speed is relatively slow, and the color of the passivation film is relatively light.

    3. The passivation solution is not stirred or the stirring force is not enough.When the passivation solution is not stirred or the stirring force is not enough during the production process, the workpiece will rise slowly locally, or the black film on the edge part is normal, and the middle part is not black.It should be appropriate to increase the air stirring or strengthen the stirring force in the passivation solution, so that the workpiece can obtain a uniform black passivation film layer.

    4. The passivation time of the workpiece is too short.The passivation time is short, and the workpiece cannot get a good black passivation film, so the passivation time of the workpiece should be appropriately extended.

    Therefore, in the production process of using galvanized trivalent chromium black passivator, we can solve the problem of slow passivation and coloring of galvanized workpieces through these four points.If you are interested in galvanized trivalent chromium black passivator,please contact Bigolly customer service, you can get free samples and detailed technical information!   
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