1. Reduce porosity, the formation speed of crystal nucleus is greater than the growth rate, which promotes the refinement of crystal nucleus.
2. Improve the bonding force and make the passivation film break down, which is conducive to the firm bond between the substrate and the coating.
3. Improve the coverage and dispersion ability. The high negative potential of the cathode allows the passivated parts of ordinary electroplating to be deposited, and slows down the "scorching" and "dendritic" of the protruding parts of complicated parts due to excessive consumption of deposited ions. The deposited defects can be reduced to 1/3~1/2 of the original thickness to obtain a given characteristic of the coating (such as color, no porosity, etc.), saving raw materials.
4. Reduce the internal stress of the coating, improve lattice defects, impurities, voids, tumors, etc., easily obtain crack-free coatings and reduce additives.
5. It is beneficial to obtain alloy coating with stable composition.
6. Improve the dissolution of anode, without anode activator.
7. Improve the mechanical and physical properties of the coating, such as increasing the density, reducing the surface resistance and volume resistance, improving toughness, wear resistance, and corrosion resistance, and controlling the hardness of the coating.
