Factors affecting the brightness of electroplated black zinc passivation layer

Factors affecting the brightness of electroplated black zinc passivation layer

Thu Apr 18 08:14:50 CST 2024

The brightness of an electroplated black zinc passivation coating is influenced by a number of factors. A passivation coating is a thin conversion coating applied after electroplating that provides additional protection against corrosion and imparts a certain color and luster to the metal surface. The following are some of the factors that may affect the brightness of an electroplated black zinc passivate coating:

1. Composition of black zinc passivation liquid: The chemical composition of the passivation film layer has a significant impact on the final appearance and brightness, including the active substance in the passivation liquid, pH value and temperature.

2. Coating quality: The brightness of the passivation film first depends on the quality of the underlying zinc coating. The flatness, gloss and purity of the coating surface will affect the appearance of the passivation layer.

3. Control of the black zinc passivation process: The time, temperature and degree of agitation of the passivation reaction must be strictly controlled to ensure the uniformity and appearance of the film layer.

4. Water quality and cleaning: The quality of the water (deionized or demineralized water quality) and the effectiveness of the cleaning step are critical to the brightness of the passivated film layer. Residual ions or contaminants can affect the appearance of the layer.

5. Passivation post-treatment: After the passivation process, the metal surface needs to be thoroughly cleaned and dried. Improper drying can leave water marks or other markings that affect brightness.

6. Environmental conditions: Environmental conditions during passivation, such as relative humidity and contamination levels, may also have an impact on the final results.

7. Hanging and arrangement of plated parts: Hanging and arrangement of plated parts can result in uneven liquid drainage or bubble build-up, which affects the uniformity and brightness of the passivated coating.

8. Black zinc passivator: The additives used in Bigely black zinc passivator often have the function of regulating the gloss of the coating.

Managing and maintaining all parameters of the passivation process improves the brightness and overall performance of black zinc passivate layers. Regular testing and adjustment of the passivate as well as optimization of the operating procedures are essential to ensure consistent high quality passivate film brightness. For this reason, our customers are offered technical consulting services by our technical engineers when using Bigely black zinc passivator.

If you have any demands for black zinc passivator, please feel free to contact us.