The requirements for electrical contact materials vary depending on the application. As a result, a wide range of electrical contact materials have been developed for different conditions of use. In fixed contacts, the main requirement for electrical contact materials is a low and stable contact resistance, especially for electrical connectors in weak power technology, which must be resistant to various environmental stresses. For sliding electrical contacts, the main focus is on improving the material’s resistance to friction and wear. For separable electrical contacts, due to the gas discharge phenomenon between the contacts and the mechanical effect during the operation of breaking and switching on the circuit, the requirements for the electrical contact materials are very demanding, and they are also the most attention-grabbing electrical contact materials.

In switching appliances, electrical contacts directly undertake the function of breaking and turning on the circuit and carrying normal operating current or carrying overload current for a certain period of time. The key functions of all kinds of electrical appliances, such as the on-off capability of power distribution appliances, the electrical life of control appliances, the reliability of relays, all depend on the performance and quality of the contacts. At the same time, the contact is also the weakest link in the switching appliances and the part that is prone to failure. Once the contact system can not work properly, such as when the power system short-circuit, such as high-voltage disconnecting contacts refused to disconnect, will cause extremely serious consequences.

Therefore, not only do different forms of electrical contact have different requirements for electrical contact materials, but even the same form of electrical contact must have different multifaceted properties when it performs different functions. In any operation process of electric al contact, various phenomena often overlap with each other, so it is necessary to consider the interrelationship of the various phenomena occurring, which is exactly where the difficulty lies in the theoretical study of electrical contact and the development of new electrical contact materials.