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Copper Plating Introduce
  • 2021-05-27 17:31:36

Copper plating is one of the most widely used pre-plating layers in the electroplating industry, including soldering parts, lead-tin alloys, and zinc die-casting parts that must be plated with copper before nickel, gold, and silver are plated to improve the bonding force of the plating.

It is used for casting molds, nickel plating, chrome plating, silver plating and gold plating, repairing worn parts, preventing local carburization and improving conductivity.

Divided into two methods: alkaline copper plating and acid copper plating. Usually, in order to obtain a thinner, fine and smooth copper plating layer, steel and other parts with oil rust removed from the surface are used as the cathode, and a pure copper plate is used as the anode, which is hung in alkaline electroplating containing copper cyanide, sodium cyanide and sodium carbonate. In the solution, perform alkaline (cyanide) copper plating.

In order to obtain a thicker copper plating layer, the plated parts must be alkaline copper-plated first, and then placed in an electrolyte containing copper sulfate, nickel sulfate, and sulfuric acid for acid copper plating. In addition, there are non-cyanide electrolytes prepared with pyrophosphate, tartrate, and ethylenediamine. Pyrophosphate electrolyte has been widely used.


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