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During the use of plating line, some problems often arise. This article focuses on introducing several common faults for you, let’s have a look at !

1. Pitting. Pitting is caused by dirty workpieces and plating solution. The characteristic is convexity, no shiny phenomenon, and no fixed shape.

2. Pinhole. The pinhole is due to the adsorption of hydrogen gas on the surface of the plated piece, which is delayed in release. When there is a lack of wetting agent in the plating solution and the current density is high, it is easy to form pinholes.

3. Airflow stripes. The airflow streaks are caused by excessive additives, high cathode current density, and high complexing agent. If the flow of the plating solution was slow at that time, the cathode would move slowly, and the hydrogen gas would rise against the surface of the workpiece, affecting the arrangement of the electrodeposition crystallization, forming streaks of airflow from bottom to top.

4. Plating brittleness. The reasons for brittleness are mostly due to excessive additives, brighteners, or inorganic substances in the plating solution. Too many organic impurities cause it. When cracks occur between the nickel layer and the substrate, it is determined that the nickel layer is brittle. When cracks between the tin layer and the nickel layer, it is determined that the tin layer is brittle.

5. Masking. Masking is due to the fact that the soft overflow material at the pin position on the surface of the workpiece has not been removed, making it impossible to carry out electrodeposition coating here.

6. Gas pocket. The formation of gas pocket is due to the shape of the workpiece and the conditions of gas accumulation. When plating, paying attention to the direction of the workpiece hook can avoid the phenomenon of gas pockets.

7. A "tin flower" opens in the center of the plastic sealed black body. There is a tin coating on the blackbody, which is because the upward parabolic shape of the gold wire is too high when the electronic tube is soldering the wire. When the gold wire is exposed on the surface of the blackbody during plastic packaging, the tin is plated on the gold wire, like a flower blooming.

8. Solder wicking. This is because during the pre-treatment of plating, the SMD frame is brushed with a copper brush, and the worn copper powder embedded in the black body is not easy to wash off, forming a conductive "bridge". During plating, as long as the electroplated metal builds the "bridge", it extends, and the dendritic deposit creeps out to connect with other copper powder, resulting in an increasing area of solder wicking.

9. Tin whisker. This is because the SMD framework is not tightly masked when silver plating is used, and silver is also plated in areas where silver plating is not required. During plastic packaging, some silver layers are exposed outside the blackbody. During the pre plating treatment, the silver layer is pried up, and the tin plated on the silver is like whiskers or piles of tin. Overcoming the exposure of the silver layer is one of the key techniques for masking silver plating.

10. Orange peel coating. When the substrate is very rough, or there is corrosion during the pre-treatment process, or when the Ni42Fe+Cu substrate is treated before plating, some copper layers have been removed, while some areas of the copper layer have not yet been removed, resulting in uneven surface blooming.