Properties and uses of copper plating:
The copper plating layer has a beautiful rose color, is soft in nature, rich in ductility, easy to polish, and has good thermal and electrical conductivity. However, it is susceptible to oxidation in the air and quickly loses its luster, making it unsuitable as a “surface” layer for protective-decorative coatings.
Copper plating is mainly used as the “under” layer in the multi-layer plating of iron and steel parts. It is also often used as the “under” layer in tin, gold and silver plating. Its role is to improve the base metal and the surface or (or intermediate) plating. The binding force also facilitates the deposition of surface coatings. When the copper plating layer is non-porous, the corrosion resistance of the surface plating layer can be improved. For example, the plating process using thick copper and thin nickel in protection-decorative multilayer plating has the advantage of this and can save precious metal nickel.
Properties and uses of nickel plating:
Nickel metal has a strong passivation ability, which can quickly form a very thin passivation film on the surface of the part, which can resist the corrosion of the atmosphere and certain acids, so the stability of nickel plating in air is very high. In a simple salt electrolyte of nickel, a very finely crystalline coating can be obtained, which has excellent polishing properties. The polished nickel coating has a mirror-like gloss while maintaining its gloss in the atmosphere for a long time. In addition, nickel plating also has high hardness and wear resistance. According to the nature of nickel plating, it is mainly used as the bottom, middle and surface layers of protective-decorative coatings, such as nickel-chrome plating, nickel-copper-nickel-chrome plating, copper-nickel-chrome plating, and copper-nickel plating Wait.
Due to the high porosity of the nickel plating layer, it is non-porous only when the thickness of the plating layer is above 25 μm, so the nickel plating layer is generally not used as a protective plating layer.
The production of nickel plating is very large, and the amount of nickel consumed by nickel plating accounts for about 10% of the total nickel output in the world.
