Manufactured by a process involving pressing, sintering, and infiltrating with copper or silver under strictly controlled conditions, Tungsten based composites are strong refractory metal materials with superior heat, electric arc, wear and deformation resistance at high-temperature welding, flash butt, and spot welding. They have also excellent electrical and thermal conductivity. The properties of Tungsten composites vary according to the copper/silver-to-Tungsten ratio. If the Tungsten content improves, the electric arc and wear resistance will increase while the thermal and electrical conductivity, on the contrary, reduce.

Due to their unique properties, Tungsten based composites are widely used where the combination of good electrical and/or thermal conductivity and low thermal deformation is necessary, for example:

• In electric resistance welding as electrical contacts or heat sinks.
• In electrodes for electrical discharge machining (EDM) and electrochemical machining (ECM).

Tungsten Silver Composite Physical and Mechanical Properties:

AgW75 is one of the high refractory content Tungsten-silver materials made by press-sinter-infiltration and normally has a high resistance to arc erosion. It is generally used as arcing contacts in large air and oil circuit breakers, line disconnects, re-closures, and in high current switches and contactors. Contact resistance is low enough to protect the higher conductivity current carrying contacts from arc damage. Its resistance to welding makes it a good shorting contact for bimetal protection in circuit breakers.

AgW70 and AgW50 have more silver than AgW75, which provides higher conductivity and a lower contact resistance. They are used extensively in a large variety of circuit breakers. In this application, a single pair of contacts provides the dual function of carrying the current without overheating and interrupting the current without excessive arc erosion. They are also used in high-current contactors where resistance to contact welding and arc erosion are required. In a variety of DC applications, they offer resistance to metal transfer.

AgW50 has the highest silver content of the press-sinter-repress Tungsten-silver materials. It exhibits good resistance to contact welding and is used for current-carrying contacts in power circuit breakers that encounter high momentary currents.

Tungsten Carbide Silver

Tungsten carbide silver composites are with a higher hardness but lower electrical conductivity than the silver Tungsten grades. They are suitable for air-switching operations where a high arc and mechanical wear resistance are required. They are used in DC switchgear, miniature circuit breakers a heavy-duty relays.

We can supply AgWC60 and AgWC72 materials.

Tungsten-Silver products: