Common problem

The influence of potassium chloride content in the bath on the bath during the application of acidic zinc plating additives

2021-07-30

In the process of using Acid zinc plating additives, the potassium chloride in the plating bath mainly plays a conductive role. During the production process, the concentration of potassium chloride in the plating bath must be strictly controlled. What effect does the concentration height have on the plating bath? ?

Bigley Technology analyzed the characteristics of acid zinc plating additive BZ-528 based on field experience and the product. The concentration of potassium chloride should be controlled within the scope of the process. It is not good if the concentration is too high or too low. If the potassium chloride concentration is too high, it will cause the brightener to salt out; if the concentration is too low, it will affect the conductivity of the plating solution, and it will also affect the dispersion and depth capabilities of the plating solution. The allowable current density range will decrease, and the coating’s Brightness will also be affected. Generally, in the plating solution using BZ-528, when the ratio of potassium chloride concentration to zinc chloride concentration is 4.5~5.0, the dispersion ability and depth ability of the plating solution are the best.

Acidic zinc plating additives

The conductivity of the plating solution does not increase with the increase of the potassium chloride concentration, but has an appropriate range. Experienced operators do not add potassium chloride according to the results of the analysis and testing. The reason is that the concentration of chloride ions is analyzed, and then converted to the concentration of potassium chloride. During the production process, it will be due to the pretreatment of hydrochloric acid. Bringing and adjusting the pH value of hydrochloric acid will cause the false appearance of high potassium chloride concentration in the analysis.

In addition, potassium chloride should be electroplating special grade, and agricultural potassium chloride cannot be used. The reason is that agricultural potassium chloride has many impurities, and the use of workpiece plating solution in the plating solution is prone to whitening and blooming.

Therefore, in the process of using acidic zinc plating additives, potassium chloride should be of good quality and brand, and the concentration of potassium chloride should be controlled within the process range to ensure that the workpiece has bright coating, high current efficiency, and coating deposition speed. Fast, good dispersion and uniformity. If you are interested in brighteners for alkaline zinc plating, please contact Bigley customer service for free samples and detailed technical information!

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