In our production process using nickel plating additives, the plating solution is often contaminated by copper ion impurities, especially the plating solution produced by barrel nickel plating.So where do these copper ion impurities come from?
Bigolly Technology made an analysis based on the field experience and the characteristics of the product's nickel plating additives Ni-301,When the workpiece is transferred from the copper plating tank to the nickel plating tank, the workpiece with a large amount of water will bring more copper ion impurities into the nickel plating solution.So what is the effect of copper impurities on the electroplating solution?
When the copper impurity content in the nickel bath is low, the coating in the low current density area of the product will be dark and rough;When the copper impurity content is high, the coating in the low current density region can be blackened and a spongy coating will appear.Generally, the copper impurity content in the bright nickel plating solution is not allowed to exceed 0.01g/L. The common nickel plating solution has a slightly higher pH value, but the copper impurity content cannot exceed 0.3g/L.
Copper impurities in nickel baths can be removed by low-current electrolysis:The pH value of the plating solution was adjusted to 3.0, and an electrolytic plate was used as the cathode. Under the condition of stirring, electrolysis was performed at a cathode current density of 0.05~0.3A/dm2.
Although electrolytic treatment is economical and practical, it will delay production and be troublesome. It is recommended to use Ni-393 copper remover from Bigolly Technology to treat copper impurities.It can have a significant effect on low-zone blackening caused by copper impurities, and does not require production shutdown.Ni-393 copper remover can quickly coordinate and combine with copper impurities in nickel plating solution to form precipitation, so as to achieve the purpose of removing copper impurities.Each 1 ml of Ni-393 can handle 10~20ppm of copper impurities, and long-term use can prevent excessive accumulation of iron ions in the plating solution.
Therefore, in the production process of using nickel plating additives, it is necessary to deal with copper impurities in the plating solution in time.Controlling the content of copper impurities in the plating solution and maintaining good stability of the plating solution can effectively reduce the occurrence of failures.
If you are interested in nickel plating additives, please contact Bigolly customer service to get free samples and detailed technical information!
If you want to know more about galvanizing, you can check "Electroplating encyclopedia".
