In the production process of using sulfate tin plating brightener, sometimes the current density of the workpiece is normal when it is first electrified. After a while, the current gradually decreases while the voltage increases. This is due to passivation of the anode plate, which reduces the efficiency of the anode current and prevents production from continuing. How can the anode plate be passivated?
Bigely Technology has conducted an analysis based on on-site experience and product characteristics, mainly for the following two reasons:
1.The purity of the anode plate used is low. The purity of the anode plate is insufficient, and it is prone to passivation during use, resulting in phenomena such as fogging of the workpiece coating. High purity tin anode plates (above 99.5%) should be replaced to prevent anode passivation.
2.The anode area is small. The area of the tin anode plate should not be too small, and the ratio of the anode and cathode areas should be around 1:1. When the ratio of anode to cathode area is less than 1:0.5, the anode plate will be passivated due to excessive current, resulting in a decrease in current efficiency and a rapid decrease in the concentration of the main salt in the plating solution.
So, in the production process of using sulfate tin plating brightener, when the anode plate is passivated, the passivation film on the surface of the anode plate should be brushed in time, and then rinsed clean with pure water before reuse. In addition, the area of the anode plate should be appropriately increased or the area of the cathode should be reduced to avoid passivation of the anode. If you are interested in sulfate tin plating brightener, please contact Bigley customer service for free samples and detailed technical information!
