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For most electrical contact applications gold alloys are used. Depending on the alloying metal the melting is performed either under in a reducing atmosphere or in a vacuum. The choice of alloying metals depends on the intended use of the resulting contact material. The binary Au alloys with typically <10 wt% of other precious metals such as Pt, Pd, or Ag or non-precious metals like Ni, Co, and Cu are the more commonly used ones <xr id="tab:tab2.2"/> ''(Table 2.2)''. On one hand these alloy additions improve the mechanical strength and electrical switching properties but on the other hand reduce the electrical conductivity and chemical corrosion resistance <xr id="fig:fig2.2"/>''(Fig. 2.2)'' to varying degrees.
Under the aspect of reducing the gold content ternary alloys with a gold content of approximately 70 wt% and additions of Ag and Cu or Ag and Ni resp., for example AuAg25Cu5 or AuAg20Cu10 are used which exhibit for many applications good mechanical stability while at the same time have sufficient
resistance against the formation of corrosion layers <xr id="tab:tab2.3"/>''(Table 2.3)''.
<div id="multiple-images">
<figtable id="tab:tab2.2">
[[File:Physical Properties of Gold and Gold-Alloys.jpg|right|thumb| Tab 2.2 Physical Properties of Gold and Gold-Alloys]]
[[File:Influence of 1-10 atomic of different.jpg|right|thumb|Fig 2.2 Influence of 1-10 atomic% of different alloying metals on the electrical resistivity of gold (according to J. O. Linde)]]
</figure>
'''Tab.2.3: Mechanical Properties of Gold and Gold-Alloys'''
<figtable id="tab:tab2.2">
{| class="twocolortable" style="text-align: left; font-size: 12px"
|-
|190<br />225<br />260<br />270<br />280
|}
</figtable>
Other ternary alloys based on the AuAg system are AuAg26Ni3 and AuAg25Pt6. These alloys are mechanically similar to the AuAgCu alloys but have significantly higher oxidation resistance at elevated temperatures ''(Table 2.4)''.
