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Tungsten and Molybdenum Based Materials

32 bytes removed, 16:05, 28 April 2014
Silver–Molybdenum (SILMODUR) Materials
=== Silver–Molybdenum (SILMODUR) Materials===
Ag/Mo materials with typically 50-70 wt% molybdenum are usually produced by the powder metallurgical infiltration process <xr id="fig:fig2.137"/> (Fig. 2.137) <xr id="fig:Physical Properties of-Contact Materials Based"/> (Table 2.36)''. Their contact properties are similar to those of Ag/W materials <xr id="tab:tab2.37"/> (Table 2.37). Since the molybdenum oxide is thermally less stable than tungsten oxide the self-cleaning effect of Ag/Mo contact surface during arcing is more pronounced and the contact resistance remains lower than that of Ag/W. The arc erosion resistance of Ag/Mo however is lower than the one for Ag/W materials. The main applications for Ag/Mo contacts are in equipment protecting switching devices <xr id="tab:tab2.38"/> (Table 2.38).
'''Table 2.36<figure id="fig: Physical Properties of -Contact Materials Based on Silver–Tungsten (SIWODUR), Silver–Tungsten Carbide (SIWODUR C) and Silver Molybdenum (SILMODUR)'''">
[[File:Physical Properties of-Contact Materials Based.jpg|right|thumb|Physical Properties of Contact Materials Based on Silver–Tungsten (SIWODUR), Silver–Tungsten Carbide (SIWODUR C) and Silver Molybdenum (SILMODUR)]]
</figure>
<xr id="fig:fig2.134"/> Fig. 2.134: Micro structure of Ag/W 25/75