Plating pre-treatment is a critical step in ensuring plating quality, and degreasing is an integral part of it.
Author: Anna
The core reason why plating equipment needs to be degreased is that grease can seriously affect plating quality. Plating pre-treatment is a critical step in ensuring plating quality, and degreasing is an integral part of it. The presence of grease can lead to a weakening of the bond between the plating layer and the substrate, thus affecting the corrosion resistance and service life of the plating layer.
Specifically, grease reduces the wettability of the plating solution, which prevents the plating solution from uniformly covering the surface of the workpiece, resulting in pinholes, bubbles and other problems in the plating layer. In addition, grease increases the resistance of the plating solution, affecting the uniform distribution of the current, which in turn affects the uniformity and brightness of the plating layer. More importantly, the presence of grease reduces the bonding of the plating layer to the substrate, causing the plating layer to peel off easily and affecting the service life and safety of the product.
In order to effectively remove grease from the surface of workpieces, commonly used degreasing methods include chemical degreasing and electrochemical degreasing. Chemical degreasing uses saponification and emulsification in an alkaline solution to remove grease, while electrochemical degreasing reduces the interfacial tension between the oil and the solution through electrolysis, making the grease easy to be stripped and dispersed in the solution.
Electrochemical degreasing process, the workpiece as the anode or cathode, through electrolysis to produce gas, these gases adsorbed on the surface of the oil film, with the increase in the number of bubbles and growth, the oil film will be torn into small oil droplets and brought to the surface of the liquid, so as to realize the complete degreasing.