Tungsten Copper Used in Vacuum Switch

Tungsten copper composite material has high hardness, high melting point, high strength and sweating property so that it can be widely used in high temperature, military fields, aeronautics and astronautics, vacuum switch, electronic packaging, EDM electrode and so on. Here we highlight tungsten-copper composite material in vacuum switch electrical aspects. Theoretically, vacuum switch is a kind of pressure in the vacuum system for the protection of the automatic controller, small size, excellent performance, stability, ease of maintenance and long service life. It can be widely used in various industrial automation environments, such as water utilities, petrochemicals, railways, military, pipelines, ships and so on.

When the vacuum pressure is greater than the set point, the controller will automatically cut off the circuit, signals, to ensure the normal operation of the system. When the pressure in the system is higher or lower than the safe pressure, pressure sensor immediate action within the controller, the controller makes contact on or off, the device stops working; When the pressure within the system to a safe pressure range of the device, the pressure sensor inside the controller reset immediately, the contacts within the controller turned on or off, the device is working properly. In order to adapt some high-voltage as well as vacuum switch electrical demand, related researchers developed special vacuum switch of tungsten copper. It can be perfectly adapt to flammable, explosive, high temperature and low temperature, moisture, corrosive environments, and gradually dominate the high-voltage (6-35V) grid and electrification equipment.

Tungsten copper composite materials require extremely low gas containing impurities (such as oxygen O2, N2 gas, etc.), it requires the use of a low gas content of raw materials and special process (high temperature sintering, vacuum infiltration, vacuum degassing, etc.) prepared. n these vacuum tungsten copper contact materials, in addition to conventional grades, the proportion of copper tungsten contact material has also developed a number of high-low tungsten copper tungsten copper, tungsten W is usually its content> 85%, such as W-10Cu, W-15Cu, etc., when asked tungsten copper material used in the case of low value when the closure, which can also add some other low melting point metal (such as antimony Sb, bismuth Bi, tellurium Te).

In contrast, there is a high copper content (60% -90%) of tungsten copper alloy, wherein W-70Cu Tungsten copper alloy products have been tested and Vickers hardness reaches1100MPa and 80% -85% IACS of high conductivity, and at 600 ℃ can still maintain a high hardness and conductivity, stable performance. Therefore, It also gradually replace some of the precious metal contacts (such as silver contacts, etc.), which significantly reducing the cost of the contact material. Overall, with the application of tungsten-copper composite materials more widely, for its new tungsten copper alloy materials research is also developing, such as tungsten copper with gradient structure, nano-crystalline tungsten copper, tungsten copper deformation processing, tungsten copper used in vacuum, tungsten copper with high or low content of tungsten, which replace the conventional materials in EDM, micro electronics, high temperature, military fields gradually. However, there are some problems of tungsten copper products in china, includes less high-end products, low utilization, the research and production are disjoint.