What’s the factor affecting the quality of electroplating layer? (II)

2. External factors

The lectroplating quality is not only affected by the electroplating process and the internal steps of the electroplating workshop, but also by other production links and technical departments. These factors are often ignored easily. We should have a comprehensive understanding of these factors.

(1) Design factors

Designers often only pay attention to the shape, size, processing accuracy and other factors of the product parts in the drawing design, and do not consider much of the processing technology, especially the electroplating process, which brings a lot of unnecessary troubles. At the same time, it also has a certain impact on the quality of the product.

1. The influence of the shape of the part.

The dispersing ability of the electrolysing solution is extremely low. The current concentration in the corners and point of the parts is easy to cause local defects such as burrs, scorching, and caking. For more complicated shapes, the deep recesses and inner surfaces ofen have less plating. Although we have solutions to obtain coatings as uniform thickness as possible, this will inevitably bring great troubles to the electroplating process and the cost of electroplating will greatly increase. Therefore, designers should consider comprehensively during the design process.

2. The drawing is not marked clearly.

Traditionally, we should indicate which part should be plated on the drawings. However the main electroplated surfaces are not clearly indicated that makes the specific operation easy to cause confusion. For the main parts, the electroplating process must ensure the internal and external quality of the coating, and there should be no obvious chromatic aberration. Therefore, only when the main and minor parts are marked on the drawing, can the non-plated parts be properly insulated and protected during the electroplating process to ensure the quality of electroplating.

(2) Surface factors before plating.

The surface quality of parts before electroplating seriously affects the quality of electroplating. A coating formed on a flat and smooth surface is always better than a rough surface. Machining processes before electroplating is only to ensure that the size, shape tolerance, surface finish are qualified. And the rust, oxide, dirt, bumped surface of the parts will cause the appearance problem after electroplating.

(3) Storage and packaging factors

Under atmospheric conditions, ferrous metals are coated with zinc to prevent corrosion. However, when the zinc coating comes into contact with phenolic paint, alkyd paint, phenolic plastic, damp wood, plywood, etc., the corrosion of the zinc coating is quite serious. The longer the time, the thicker the corrosion. The acceleration of corrosion is called atmospheric corrosion. The organic volatile atmosphere can corrode the zinc coating only in a humid atmosphere. If there is only a corrosive atmosphere and the surrounding air is very dry, there will be basically no corrosion. Therefore, in the atmosphere, only when there is no organic volatile atmosphere or completely dry air under certain conditions, zinc coating is a reliable protective coating. In the storage process of qualified products, we need to make sure a dry the environment of the warehouse to avoid atmospheric corrosion. In addition, during transportation, we also should pay more attention to the product packaging; it directly affects the corrosion resistance of parts.

We ignore easily these external factors, which become an important factor affecting the quality of electroplating.