Analysis Of Composite Plating Process For Copper Terminal Blocks

In connector manufacturing, surface treatment processes directly determine the environmental adaptability and assembly reliability of components. To meet the practical needs of power transmission and signal control scenarios, engineers have continuously iterated on the surface treatment solution for copper terminal block.

Multi-layer plating structure design

The composite plating of copper distribution block tin and nickel balances corrosion resistance and weldability. This plating system is achieved through a precise electrodeposition process. The nickel layer, as the bottom layer, is preferentially deposited on the copper terminal strip substrate surface. Its dense crystalline structure forms a robust barrier, effectively isolating external moisture and corrosive media, significantly improving the service life of the copper terminal block under harsh operating conditions.

Surface Process and Performance Subdivision

• Functional Positioning of the Tin Plating Layer: The outer tin plating layer undertakes another key technological mission. Tin metal has good ductility and a low electrochemical potential. During the brazing operation between the copper terminal block and the connecting wires, the tin layer can quickly melt and spread, forming a reliable intermetallic interface.

• Synergistic Effect of the Composite Interface: The nickel and tin layers are not simply stacked. In the post-processing stage, an extremely thin nickel-tin alloy diffusion layer is formed between the two layers. This transition structure enhances the adhesion between the coatings and prevents coating peeling caused by thermal or mechanical stress.