pvd coating machine precious metal coating alternative process, reduce precious metal consumption and adopt electroplating process that replaces precious metal. The more mature ones are ternary alloy plating instead of silver plating.

       (1) Ternary alloy instead of silver coating
       The copper-tin-zinc ternary alloy coating has a bright silver-white color and has better anti-tarnishing performance than silver plating. Therefore, connectors used for external assembly in the electronic connector industry are generally used instead of silver plating. At this time, the appearance is mainly adopted. The color is self-bright and not easy to change color, and the inner conductor is still silver-plated to ensure that the conductivity is not greatly affected.
       The process flow of the ternary alloy is as follows: self-inspection, mounting, chemical degreasing, washing, washing, ultrasonic degreasing, hot water washing, washing, acid etching, washing, washing, electrochemical degreasing, washing, washing, washing, activation~washing One water wash, pre-copper plating, water wash, water wash, activation, acid copper plating, water wash, water wash, ternary alloy plating, pure water wash, water wash, hot water wash, drying, self-inspection and inspection.
       (2) Copper plating replaces silver plating process
       Another trend is to replace silver plating with pure copper plating with conductivity second only to silver. The ternary alloy silver coating is only similar in color to the silver layer, and the conductivity is incomparable with the silver layer. At the same time, the ternary alloy still uses the cyanide plating system and requires heating, which makes it difficult to control the composition of the coating. Therefore, it is not suitable for high-conductivity occasions, especially for parts with high third-order intermodulation requirements for waveguide devices, and experiments have shown that the use of pure copper plating can replace the silver plating layer. If copper plating is used instead of silver plating for large-area microwave device products, the value of saving precious metals is very attractive. It can be seen from the table that when the DC resistance value of silver is lQ, copper is the closest to it, only 1.05Ω; the conductivity is also very close, silver 6.17*10-7 S/m and copper 5.80 respectively. *10-7S/m. Therefore, the use of copper instead of silver as the conductive coating is completely feasible in terms of conductivity.