In the production process of using nickel plating brightener, due to the certain deformation of the metal nickel crystal or the inclusion of different phases, a certain internal stress will be generated in the coating.When the internal stress of the nickel layer is large, the hardness of the coating will be relatively large, but it is easy to peel, crack or have poor ductility.So, what factors are related to the internal stress of the nickel layer?
Bigolly Technology made an analysis based on the field experience and the characteristics of the product nickel plating brightener Ni-301,there are four main points:
1. The pH value of the plating solution is abnormal.When the pH value of the plating solution increases, there will be hydrogen evolution near the cathode, which will increase the pH value, and will produce nickel hydroxide particles mixed in the coating, increasing the hardness of the coating.During production, the pH value of the plating solution should be controlled in a lower range to obtain a softer nickel plating layer.
2. The current density is too high and the temperature is too low.At high current density and low temperature, the internal stress of the nickel plating layer will increase.During production, attention should be paid to using appropriate current density and keeping the temperature of the plating solution within the process range, and the temperature should not be lower than 50 °C.
3. The influence of the composition of the plating solution.The abnormal composition of the plating solution will also affect the internal stress of the plating layer.When the main salt concentration of the plating solution is too high, especially when the chloride ion concentration is too high, the internal stress of the plating layer will increase.For example, the internal stress of full chloride nickel plating can reach 280-340N/mm2, while the internal stress of nickel sulfamate is very small, only 70N/mm2.
4. The influence of impurities in the plating solution.Impurities are a more complicated factor affecting the nickel plating layer.Impurities are difficult to control in the nickel plating process, and are often found only after they have accumulated to a certain amount.And once a fault occurs, it is more difficult to rule out.For example, organic impurities are generally the accumulation of excessive electroplating additives or the accumulation of their decomposition products. The coating is brighter, but the dispersibility is not good, and it is easy to peel, and there will be cracking in the high current area.
Therefore, in the production process of using nickel plating brightener, we should control the process parameters of the plating solution, the concentration of the plating solution components and the content of impurities.In this way, the internal stress of the coating can be avoided to affect the quality of the coating.If you are interested in nickel plating brightener,please contact Bigolly customer service, you can get free samples and detailed technical information!
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