The conductive parts of the terminal are generally made of copper alloy materials such as brass, copper, etc. In order to increase the conductivity of the conductive metal of the terminal and reduce the oxidation of metal molecules, we need to give it a surface treatment and a suitable “coat”—— Plating.
In a specific use environment, it will cause corrosion to the terminal, such as the oxidation and vulcanization of the conductive parts. The electroplated conductive parts can isolate the reed from the environment and prevent corrosion.
Electroplating materials should avoid corrosion, at least in the application environment, so the current general electroplating method uses tin-plated cerium (non-toxic process, good environmental protection effect, good mechanical strength, good corrosion resistance, good solderability), etc. .
The optimization of the terminal surface performance can be achieved in two ways. One is the design of the connection terminal, establishing and maintaining a stable terminal contact interface. The second is to establish metallic contact, requiring that any surface film layer is non-existent or will be broken during insertion.
In other words, it makes it easier to achieve metal-to-metal contact. What we have to consider is how to keep the surface of the terminal “noble”, free from external factors such as pollution, substrate diffusion, terminal corrosion, etc.
No matter the surface of the conductive parts of the terminal is plated with gold, palladium or tin and lead and its alloy plating layer, the effect is the same, only due to the different chemical characteristics of the plating layer film, corresponding to the contact strength and plug strength of the terminal metal. Will be different, thereby affecting the service life of the conductive parts.