When we use Sulfamic acid nickel additive in the production process, when the crystallization of the coating changes, a certain internal stress will be generated. When the internal stress of the coating is high, the hardness of the coating is high, it is prone to peeling, cracking, and poor ductility. So, what are the factors that affect the internal stress of the coating?
Bigley Technology has analyzed the characteristics of the nickel Sulfamic acid additive Ni-1000 based on the following five factors:
1. The influence of plating solution composition. Abnormal composition of Sulfamic acid nickel plating solution will affect the stress of the plating solution. When the concentration of the main salt is too high, especially when the chloride ion is too high, the internal stress of the coating increases. Therefore, we should control the concentration of various components in the plating solution within the process range during production.
2. The pH of the plating solution is abnormal. When the pH value of the plating solution increases, there will be a higher pH value near the cathode due to hydrogen evolution, which is easy to produce Nickel(II) hydroxide particles mixed in the coating, thus increasing the internal stress of the coating. Therefore, we should strictly control the pH value of the plating solution between 3.5 and 4.5 during production.
3. The current density is too high and the temperature is too low. Under high current density and low temperature conditions, the internal stress of the nickel plating layer will significantly increase. Therefore, we should pay attention to using appropriate current density and controlling the plating solution temperature within the normal range during production.
4. The impact of organic impurities. The organic impurities in the plating solution come from the excessive addition of additives or the accumulation of decomposition products. When the nickel plating layer is bright but has poor dispersion performance and is prone to peeling, especially in high current areas where cracking occurs, a combination of hydrogen peroxide and activated carbon should be used to treat the plating solution to remove the influence of organic impurities.
5. The influence of metal impurities. The main metal impurities in nickel plating solution are zinc and iron impurities. When the zinc impurity is greatly 0.02g/L, the internal stress of the nickel plating layer will significantly increase, and the coating will become brittle. When the content of iron impurities reaches above 0.05g/L, it can also make the coating brittle. When there are large metal impurities in the plating solution, a current electrolysis solution of 0.2-0.4A/dm2 can be used to reduce the impact of metal impurities.
Therefore, we should pay attention to the above five points in the production process of using Sulfamic acid nickel additive to ensure that the performance of the plating solution is good and that the nickel coating can also maintain low stress and good ductility. If you are interested in Sulfamic acid nickel additive, please contact Bigley customer service to obtain free samples and detailed technical information!
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