Reasons for the color of workpiece appearance in the production process of using zinc nickel alloy black passivator

Reasons for the color of workpiece appearance in the production process of using zinc nickel alloy black passivator

Wed Nov 09 08:51:02 CST 2022

    A customer inquired that during the use of zinc nickel alloy black passivator, the passivation of the workpiece was followed by sealing treatment, and the appearance of the passivation film would be colored.The workpiece is uniformly black and bright before, how can it be colored?

    According to the field experience and the characteristics of the product zinc nickel alloy black passivator Zn-327, Bigolly Technology has analyzed that the passivating film of the workpiece is colored mainly for the following three reasons:

    1. The concentration of brightener is high or the concentration of nickel supplement is low during zinc nickel alloy electroplating.When the concentration of brightener in the plating solution is too high, the appearance of the coating is too bright, and the appearance will be colored when the black passivation is carried out;If the concentration of nickel supplement is too low, the nickel content in the coating will be low, and the passivation film will be easy to be colored during black passivation.Therefore, in the production process, the concentration of brightener and nickel supplement in the plating solution can be adjusted within the process range through Hull cell experiment.

    2. After black passivation of the workpiece, the passivation film will be colored.At this time, check whether the operating coefficient of the passivation solution is correct. If the concentration of the passivation solution is too low or the pH value is too high, the passivation film will be colored.Therefore, it is necessary to ensure that the operating parameters of the passivation solution are within the process range during the production process.

    3. The low concentration of the sealing agent or the short sealing time will lead to the thin and uneven sealing film of the workpiece, which is easy to appear brittle after drying.The uniform and full sealing film can be ensured by increasing the concentration of the sealing agent or adopting two sealing treatments, namely sealing drying sealing drying process.

    Therefore, we should pay attention to these three points when the workpiece passivation film is colored during the use of zinc nickel alloy black passivator, and solve the failure as soon as possible to reduce losses.If you are interested in zinc nickel alloy black passivator, please contact the Bigolly customer service for free samples and detailed technical information!

    If you want to know more about zinc nickel alloy, you can click to view "Electroplating encyclopedia".