Tungsten Vacuum Contact

Tungsten Vacuum Contact Description

Electrical contacts build electrical connections between components in overvoltage protections, relays and switches. The requirements for the switch contacts are different depending on the switching power, switching voltage, switching frequency, continuous current, and the starting and breaking current. Accordingly, the requirements for the contacts and the methods to ensure their safe function vary. To prevent oxidation, the contacts can be made corrosion resistant by coatings with precious metals or by operating the contacts in a vacuum, inert gas or oil. Other problems include contact erosion, erosion by spark flashover, or arcing and welding at high power. These problems can be solved by using refractory metals like tungsten.

At the same time a low contact resistance must be ensured. This however can be provided by low-melting but highly conductive metals such as copper and silver. Depending on the requirement, the properties of the high melting metals are combined with those of highly conductive metals. Therefore, alloys are produced in which both components are present in a suitable ratio to each other. This creates contacts with very good welding resistance and good contact resistance.

Vacuum Contact (WCAg) Specification

We also supply our WCu switching contacts in VFG (Vacuum Fine Grained) quality. This means that they are ultrapure and have an excellent electrical conductivity. Depending on the requirements, we have various VFG materials in our range with two different copper contents:

VFG10 (tungsten 90% by weight, copper 10% by weight)

VFG20 (tungsten 80% by weight, copper 20% by weight)

Our switching contact made of WCCu30 is a cost-effective alternative to WCAg and is also manufactured from low-gas raw materials for use in a vacuum.

WCCu30 (tungsten carbide 70% by weight, copper 30% by weight)

Vacuum Contact Material Properties

Tungsten Vacuum Contact Applications and Related Industries

● Vacuum switches