Pin header and female header connector are usually coated with special coating. Generally, gold plating and tin plating are used.

In fact, the contact coating of the pin header and the female header can not only protect the pin header and the female header, reduce the corrosion of the environment, but also improve the durability and wear resistance of the pin header and the female header. It is helpful to establish and maintain stable impedance of pin header and female header through electrical performance.

At present, most contact shrapnel of pin header and female header are made of copper alloy, but copper alloy is easy to corrode in typical working environment of electrical connector. Therefore, optimizing the interface as an important function of corrosion protection is a consideration in selecting suitable contact coating materials. However, in practice, the contact coating is used to separate the contact spring from the working environment to prevent copper corrosion. In addition, the plating material of pin arrangement shall not be damaged in its working environment.

When the film thickness of pin header and female header connector increases, the resistance increases rapidly, but the film will become a poor conductor. However, the film of the pin-arranging female connector will be mechanically broken down under high contact pressure or electrically broken down under high voltage and high current. Therefore, it is not suitable to increase the film thickness when using pin header and female header connectors.