The zincate galvanizing process results in the appearance of pockmarks in the plating, which can be caused by several different factors. Pocking is a phenomenon of localized unevenness, roughness and bubbles on the surface of the plating, which may affect the overall appearance and corrosion resistance of the plating. Common causes include the following:
1. Incomplete surface cleaning: If the workpiece is not completely cleaned of surface oils, grease, oxidized layers and other impurities prior to zincate galvanizing, these residues may result in uneven coverage of the coating and the formation of pockmarks.
2. Bubble adsorption: During the galvanizing process, bubbles may be generated if the chemicals in the bath are unstable or if there are small bumps on the surface of the workpiece. These bubbles adhere to the surface of the workpiece and are sealed in as the zinc layer is deposited, forming pockmarks in the coating.
3. Uneven composition of the plating solution: If the concentration of zinc salts, other metal salts, additives and conditioners in the plating solution is not reasonably configured, it may cause an uneven deposition rate of zinc in the plating layer, which may result in pockmarks in the high areas.
4. Unsuitable process parameters: For example, the temperature of the plating solution, the current density and time during plating can affect the quality of the coating. If these parameters are not properly controlled, they may also lead to the appearance of pockmarks.
5. Workpiece Hanging Style: During the plating process, the location and angle at which the workpiece is hung may affect the liquid flow and current distribution. If the high areas of the workpiece are affected by a higher current density, this may result in excessive nickel deposition in that area, resulting in pockmarks.
6. Brightener is too much: do not follow the principle of adding less diligently, adding too much zincate galvanizing brightening agent, it is easy to produce the plating layer pockmarked.
Solving these problems usually requires optimizing the galvanizing process to ensure that the surface of the workpiece is thoroughly cleaned, adjusting the bath formulation and process parameters, and using proper suspension and agitation facilities to achieve a uniform coating.
If the problem of pitting persists when using Bigely zincate galvanizing brighteners, our technical engineers are required to perform a surface preparation analysis to diagnose the exact cause and take appropriate action.
If you are interested in zincate galvanizing brightener, please feel free to contact us.
