1, connect the function of anti-corrosion coating
Connector corrosion protection is to be considered first. Most connectors electrical contact spring is made from copper alloys and copper alloys in a typical work environments are vulnerable to corrosion of electrical connectors, such as oxide and sulfide. In fact, contact coating was used to close contact with shrapnel and separated from the work environment in order to prevent corrosion of copper. Of course, coated material in their work environment must not be damaged (at least in the context of harmful). As an important function of the corrosion protection, optimized interface touch coatings is choosing the right material for consideration.
2, the coating helps to improve the mechanical properties of the connector
Parameters associated with the mechanical properties mainly affecting the durability of coating or wear, and combining ability factor. The factors to consider are two different views of the same basic effect, namely, multi point interface in relative movement of cold welding in sharing. The most important mechanical properties, including hardness, ductility coefficient of friction and coating materials. All of these properties depends on the intrinsic properties of the coating material and the application process.
3, the coating helps to improve the electrical properties of the connector
Optimal electrical properties are available from the following considerations, which already exists and will be formed in contact with the surface coating film control. Electrical properties of electrical connectors is a main demand of establishing and maintaining a stable connector impedance. For this purpose, you need a metal contact interface to provide inherent stability. Establishing this interface when you need to meet a film on the surface in contact with bypass or split. The two different options identified precious metals or the difference between precious metals and common metal.
4, connector usage characteristics of precious metal plating
In varying degrees, precious metal plating (gold, Palladium, and their alloys), the essence of which is free to the surface film. For these coatings, metal contacts interface is relatively simple, because it only needs to contact surface with the co-ordination of movement. Usually this is easy to do. Interface impedance stability to maintain contact, connector design requirement should keep contact surfaces of precious metals to prevent external factors such as pollutants, spread and influence of contact wear of the base metal.
5, the connector uses the General characteristics of metallic coatings
Common metal coating, especially Tin and Tin alloys, which are naturally covered in a layer of oxide film. Contact coating of Tin, because this layer of oxide is easily at match time was destroyed, so that the metal contact is easy to set up. Electrical connector design requirement is to ensure that the oxide film rupture in the connector, and continuous dedication to ensure the validity of contact interface no longer be oxidized. Oxidation and corrosion, wear and corrosion, contact is tin plating most major performance degradation mechanisms. Silver coating is the best contact as a normal metal cladding, because the deposits were vulnerable to corrosion of sulfide and chloride. Since the formation of valves are usually deemed to be nickel plated base metal.