In the production process of using nickel plating brightener, the plating solution is weakly acidic. During the nickel plating process, in addition to the deposition of nickel layer on the workpiece of the cathode, a small amount of hydrogen gas is also released. The release of hydrogen gas will affect the concentration of hydrogen ions in the plating solution and also affect the pH value of the plating solution. So, controlling the pH value of the plating solution is an important factor affecting the quality of the coating.
In various formulations of nickel plating brighteners, the pH control range in the plating solution varies depending on the composition and content of the plating solution. When the nickel sulfate content in the plating solution is high, the pH value can be controlled to be lower; When the nickel sulfate content is low, the pH value can be correspondingly higher.
The pH range of the plating solution should be controlled within the process range, for example, the pH value of Bigely's nickel plating brightener should be controlled between 4.2 and 4.8. When the pH value of the plating solution is too low, the current efficiency of the cathode decreases, the brittleness of the coating is relatively high, and sometimes there is no coating, only hydrogen gas is released. When the pH value is too high, the plating solution will become turbid, and the deposited coating will have problems such as fogging, burrs, and brittleness.
If the pH value in the plating solution is too high, 10% sulfuric acid can be used for adjustment. If the chloride ion in the plating solution is too low, 1:1 hydrochloric acid can also be used for adjustment. When the pH value of the plating solution is low, 5-10ml of sodium hydroxide or potassium hydroxide solution can be used for adjustment. Attention should be paid to adding slowly and stirring strongly when adding to avoid the formation of nickel hydroxide precipitation due to local high pH values.
So, in the production process of nickel plating by rolling, controlling the pH value of the plating solution can reduce the failure rate, improve production quality, and better use nickel plating brighteners. If you are interested in nickel plating brightener, please contact Bigely customer service for free samples and detailed technical information!
