Views: 267 Author: Site Editor Publish Time: 2022-02-17 Origin: Site
We know that gold plating has a history of more than one hundred years. Gold plating and silver plating are all to protect the integrity of electronic contacts and avoid arc damage, adhesion, and oxidation of contacts caused by excessive current at the moment of switching on and off. The molecular activity of gold and silver is the largest, and gold is more active than silver. Therefore, electrical contacts with gold plating are essential for some devices which have high technical requirements. And the current efficiency of various gold plating solutions is different, and the deposition speed of the gold plating solution with different current efficiencies is different. Then what is the thickness of gold plating for contacts and connectors?
Generally speaking, the thickness of gold plating for connector and metal contact applications is the main factor for design consideration. For connectors which need high reliability and durability, gold plating is a special and essential finish, since it will affect the durability and ultimate cycle life of the connector. Gold plated contacts and connectors have some advantages such as low contact resistance which suit for applications with low signal voltages and current in the millivolt and milliamp range. Maybe some people are wondering that gold is a precious metal, and the price is more expensive than other common metals, which will cause the cost increased. The key is that it does not react with chemicals in most environments. It means that only the thickness of gold plating can provide a sufficient barrier for the substrate and environment since its conductivity for contacts and connectors will be weakened by over time.
Considering of the cost, gold plating layer of contacts and connectors is very thin comparing with other plated metals, and the thickness is typically 5uin to 100uin (0.1um-25um). Only in extreme cases, the thickness of gold layer can be plated 500uin to 1000uin (12.5um to 25um). Of course, the corrosion resistance and wear resistance of the gold plated connector will increase when the thickness of gold player is increased. If the thickness of connectors plated thin gold is less than 10uin (0.25um), you may see the surface of contacts and connectors is porous. And thousands of microscopic pores like a thin gold screen deposited on the surface of connectors instead of continuous pore-free layer. For this reason, it will be easy to make the substrate to be oxidized and corroded through the pores of surface, though the gold plating can avoid reacting to corrosive environments too some extent.
But there is one way that can improve obviously gold connectors from being oxidized and corroded, that is to increase the thickness of gold plating to improve corrosion protection and wear resistance of gold connector. When the thickness of gold plating increases, the pores on the surface of gold connectors will reduce. And even the pores will be closed creating a pore free gold layer as the continuous increasing of gold plating thickness, which will supply an exceptional barrier for corrosive protection. Of course, the gold plating contact cost will be more.