In the production process of using electroless nickel plating solution, sometimes the welding performance of the coating is poor. What is the reason?
According to the field experience and the characteristics of the product electroless nickel plating solution Ni-809, Bigolly Technology made an analysis, mainly including the following six points:
1. Phosphorus content of the coating.Solderability of the electroless nickel coating is inversely proportional to phosphorus content of the coating.When the phosphorus content of the coating is low, the weldability of the coating is good; When the phosphorus content of the coating is above 9%, the weldability of the coating is poor.This is because phosphorus is non-metallic. With the increase of phosphorus content, the non-metallic properties of the coating gradually improve, and the solderability of the coating is worse.
2. Influence of electroplating conditions.The obtained coatings are different under different electroplating conditions, that is, the concentration, temperature and pH value of the plating solution in the electroplating process will have a great impact on the phosphorus content.The phosphorus content decreased with the increase of temperature; With the increase of pH value, the phosphorus content of the coating decreases accordingly.Therefore, in order to obtain a coating with good weldability, all parameters in the electroplating process should be controlled within the process range.
3. Effect of coating thickness.The solderability of the electroless nickel coating is related to the coating thickness. When the coating thickness is too low, the porosity is very high, and the solder paste cannot be separated from the base metal in many places, resulting in poor welding.Therefore, the thickness of electroless nickel coating shall be more than 1 μm.
4. Effect of bath aging.With the progress of production, the bath will gradually age and the content of sodium phosphite in the bath will gradually increase.Under the same operating conditions, the phosphorus content of the coating will gradually increase, so the weldability of the coating will decline.
5. The influence of metal additives.Some electroless nickel plating solutions will add metal additives, which will greatly affect the weldability of the coating.Generally, the welding performance of the plating solution added with metal additives will be much better than that of ordinary electroless nickel plating.
6. The impact of workpiece storage time and environment.The storage time and environment of workpiece have great influence on weldability.If the workpiece is stored for a long time in acidic or alkaline environment, the surface of the workpiece will be oxidized, causing welding difficulties.
In this way, we should pay attention to the above six points in the process of using the electroless nickel plating solution, which can maintain the good weldability of the electroless nickel coating and stabilize the production efficiency.If you are interested in the electroless nickel plating solution, please contact the Bigolly customer service for free samples and detailed technical information!
If you want to know more about electroless nickel plating,you can click to view "Common problem".