2,315
edits
Changes
no edit summary
Table 2.35: Mechanical Properties of Tungsten and Molybdenum
===2.5.2 = Silver–Tungsten (SIWODUR) Materials====
Ag/W (SIWODUR) contact materials combine the high electrical and thermal
conductivity of silver with the high arc erosion resistance of the high melting
distribution.
===2.5.3 = Silver–Tungsten Carbide (SIWODUR C) Materials====
This group of contact materials contains the typically 40-65 wt-% of the very
hard and erosion wear resistant tungsten carbide and the high conductivity silver
The applications of Ag/WC contacts are similar to those for Ag/W ''(Table 2.38)''.
===2.5.4 = Silver–Molybdenum (SILMODUR) Materials====
Ag/Mo materials with typically 50-70 wt% molybdenum are usually produced by
the powder metallurgical infiltration process ''(Fig. 2.137) (Table 2.36)''. Their
and Silver Molybdenum (SILMODUR)
===2.5.5 = Copper–Tungsten (CUWODUR) Materials====
Copper–tungsten (CUWODUR) materials with typically 50-85 wt% tungsten are
produced by the infiltration process with the tungsten particle size selected
Copper (CUWODUR) Contact Materials
===2.6 Special Contact Materials (VAKURIT) for Vacuum Switches===
The trade name VAKURIT is assigned to a family of low gas content contact
materials developed for the use in vacuum switching devices ''(Table 2.42)''.
===2.6.1 = Low Gas Content Materials Based on Refractory Metals====
Contact materials of W/Cu, W/Ag, WC/Ag, or Mo/Cu can be used in vacuum
switches if their total gas content does not exceed approximately 150 ppm. In
their contact carriers ''(Table 2.44)''.
===2.6.2 = Low Gas Content Materials Based on Copper-Chromium====
As contact materials in vacuum interupters in medium voltage devices low gas
materials based on Cu/Cr have gained broad acceptance. The typical chromium
Table 2.44: Application Examples and Form of Supply for VAKURIT Materials
Vinaricky, E.(Hrsg.): Elektrische Kontakte, Werkstoffe und Anwendungen.
