What factors are related to the protective properties of the plated layer when we use acid zinc brighteners? According to Bigely many years of experience in electroplating technical service, it is related to the following two points.
Relationship between plating protection and current density
An excessive amount of acid zinc brightener can have an effect on the protective ability of the plating. This is well known.
However, there is one point that is not easily noticed by people.
That is, the increase in current density will also lead to too much brightener entrapped in the plating layer, which in turn will cause a decrease in the protective ability of the plating layer, and in the summer temperature is relatively high in the period of high current density in large-scale production, the plating layer is more prone to long white hairs, blackening and other defects.
This is why some electroplating plants, despite the use of the same kind of acid zinc brightener, some made out of the plating layer will not appear discoloration failure, salt spray resistance is better; however, some electroplating plant plating made out of the serious discoloration, in addition to the content of acid zinc brightener with the plating solution, but also can not be ruled out is the current density caused by.
Relationship between plating protection and zinc ion concentration
As we mentioned in the previous article, increasing the amount of zinc acid brightener in the plating solution will result in a decrease in the protection of the plated layer. To increase the concentration of zinc ions in the plating solution, it is necessary to increase the concentration of brightener at the same time.
As a result, the corrosion resistance of the plated layer is also reduced. For parts with high protection requirements, when plating plants use Bigely acid zinc brightener, we would recommend them to use low concentration and low current for production, so as to ensure the quality of the plated layer.
Want to learn more about acid zinc brighteners? Please contact us.
