During the process of using sulfate tin plating additives, sometimes there is an anodic polarization phenomenon, where the current decreases while the voltage increases, resulting in poor conductivity of the plating solution and affecting the coating quality of the workpiece. So what is the cause of anodic polarization?
Based on on-site experience and the characteristics of Sn-807, a sulfate tin plating additive, Bigley Technology analyzed the following three main reasons:
1. The sulfuric acid content in the plating solution is too high. Although high sulfuric acid content can slow down the hydrolysis of divalent tin and tetravalent tin, it will reduce the current efficiency of the cathode and make the anode prone to polarization. Therefore, during the production process, the sulfuric acid content in the plating solution should be analyzed and adjusted in a timely manner to ensure good current efficiency of the plating solution.
2. A small anode area or passivation of the anode plate can significantly reduce the current efficiency of the plating solution, leading to a decrease in current and an increase in voltage. Therefore, during the production process, the anode plate should be inspected to ensure sufficient anode area, and the anode plate should be cleaned in a timely manner to avoid passivation of the anode plate and affecting current efficiency.
3. There are many organic impurities in the plating solution, which will deepen the color of the plating solution, increase the viscosity, and reduce the current efficiency of the plating solution. Therefore, during the production process, activated carbon should be regularly used to treat or dilute the plating solution to reduce the impact of organic impurities.
Therefore, when the phenomenon of anodic polarization occurs during the use of sulfate tin plating additives, attention should be paid to the above three points, and faults should be eliminated as soon as possible to improve production efficiency. If you are interested in sulfate tin plating additives, please contact Bigley customer service for free samples and detailed technical information!
If you want to learn more about tin plating, you can click to view the "Common problem".