Electrical contact material, also known as contact or contact, is a high and low voltage electrical key components, charged with the role of breaking and breaking current, a direct impact on the switch, electrical reliability and service life. Tungsten copper alloy contacts in the process of burning arc, the surface of the low melting point of copper first melted, due to capillary action is adsorbed in the tungsten skeleton capillary hole, under the action of high temperature evaporation and take away a lot of heat, so that the tungsten skeleton cooling, so that The contacts have good breaking performance. Tungsten skeleton due to the high melting point, the ablation in the arc is extremely small, even if the local temperature is too high will not melt welding, thus ensuring the stability of the switch performance, reliability and long life. And the higher the tungsten content, the better the performance of anti-burn, but the conductivity is low, the specific use to be a specific choice. At present, the electrical contact with tungsten copper material in addition to conventional high-voltage electrical switch, the main development is: First, ultra-high pressure with the tungsten copper electrical contacts, that is, from 500,000 volts to 75 million volts or even 200 million volts Above the development; Second, the medium voltage with the vacuum tungsten copper material.