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The silver plating of the article is mainly to prevent corrosion, increase conductivity, reflectivity and aesthetics. Widely used in the manufacturing industries such as electrical appliances, instruments, meters and lighting appliances. For example, when copper or copper alloy parts are plated with silver, we must first degrease and rust the copper; then silver or immerse the articles in a solution prepared from mercury chloride, etc., to perform mercuryation treatment to make the parts.

The surface is plated with a mercury film; then the workpiece is used as a cathode, the pure silver plate is used as an anode, and immersed in a silver potassium cyanide electrolyte prepared by silver nitrate and potassium cyanide for electroplating. The industries such as electrical appliances and meters also use cyanide-free silver plating. In order to prevent discoloration of the silver coating, it is usually subjected to post-plating treatment, mainly immersion, chemical and electrochemical passivation, plating of precious metals or rare metals or coating layers.