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→Tungsten and Molybdenum (Pure Metals)
===Tungsten and Molybdenum (Pure Metals)===
Tungsten is characterized by its advantageous properties of high melting and boiling points, sufficient electrical and thermal conductivity and high hardness and density ''<xr id="tab:tab2.35"/> (Table 2.35)''. It is mainly used in the form of brazed contact tips for switching duties that require a rapid switching sequence such as horn contacts for cars and trucks.
Molybdenum has a much lesser importance as a contact material since it is less resistant against oxidation than tungsten.
Both metals are however used in large amounts as components in composite materials with silver and copper.
<figtable id="tab:tab2.35">
'''Table 2.35: Mechanical Properties of Tungsten and Molybdenum'''
<table border="1" cellspacing="0" style="border-collapse:collapse"><tr><td><p class="s12">Material</p></td><td><p class="s12">Micro Structure Condition</p></td><td><p class="s12">Vickers</p><p class="s12">Hardness HV 10</p></td><td><p class="s12">Tensile Strength</p><p class="s12">[MPa]</p></td></tr><tr><td><p class="s12">Wolfram</p></td><td><p class="s12">Lightly worked structure</p><p class="s12">(wire and strip > 1.0 mm thick)</p><p class="s12">Strongly worked structure</p><p class="s12">(wire and strip < 1.0 mm thick)</p><p class="s12">Re-crystallized structure</p></td><td><p class="s12">300 - 500</p><p class="s12">500 - 750</p><p class="s12">360</p></td><td><p class="s12">1000 - 1800</p><p class="s12">1500 - 5000</p><p class="s12">1000 - 1200</p></td></tr><tr><td><p class="s12">Molybdän</p></td><td><p class="s12">Lightly worked structure</p><p class="s12">(wire and strip > 1.0 mm thick)</p><p class="s12">Strongly worked structure</p><p class="s12">(wire and strip < 1.0 mm thick)</p><p class="s12">Re-crystallized structure</p></td><td><p class="s12">140 - 320</p><p class="s12">260 - 550</p><p class="s12">140 - 160</p></td><td><p class="s12">600 - 1100</p><p class="s12">800 - 2500</p><p class="s12">600 - 900</p></td></tr></table>
</figtable>
=== Silver–Tungsten (SIWODUR) Materials===
