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====Silver-Nickel (SINIDUR) Materials====
Since silver and nickel are not soluble in each other in solid form and also show very limited solubility in the liquid phase have only very limited solubility , silver nickel composite materials with higher Ni contents can only be produced by powder metallurgy. During extrusion of sintered Ag/Ni billets into wires, strips and rods , the Ni particles embedded in the Ag matrix are stretched and oriented in the microstructure into a pronounced fiber structure <xr id="fig:Micro structure of AgNi9010"/><!--(Fig. 2.75)--> and <xr id="fig:Micro structure of AgNi 8020"/><!--(Fig. 2.76)-->
The high density produced during hot extrusion , aids the arc erosion resistance of these materials <xr id="tab:Physical Properties of Silver-Nickel (SINIDUR) Materials"/><!--(Tab 2.21)-->. The typical application of Ag/Ni contact materials is in devices for switching currents of up to 100A <xr id="tab:Application Examples and Forms of Supply for Silver-Nickel (SINIDUR) Materials"/><!--(Table 2.24)-->. In this range , they are significantly more erosion resistant than silver or silver alloys. In addition , they exhibit with nickel contents < 20 wt% a low and over their operational lifetime consistent contact resistance and good arc moving properties. In DC applications Ag/Ni materials exhibit a relatively low tendency of material transfer distributed evenly over the contact surfaces <xr id="tab:Contact and Switching Properties of Silver-Nickel (SINIDUR) Materials"/> <!--(Table 2.23)-->.
Typically Ag/Ni (SINIDUR) materials are usually produced with contents of 10-40 wt% Ni. The most widely common used materials SINIDUR 10 and SINIDUR 20- and also SINIDUR 15, mostly used in north america-, are easily formable and applied by cladding <xr id="fig:Strain hardening of AgNi9010 by cold working"/><!--(Fig. 2.71)--> <xr id="fig:Softening of AgNi9010 after annealing"/><!--(Fig. 2.72)--> <xr id="fig:Strain hardening of AgNi8020"/> <!--(Fig. 2.73)--> <xr id="fig:Softening of AgNi8020 after annealing"/><!--(Fig. 2.74)-->. They can be, without any additional welding aids, economically welded and brazed to the commonly used contact carrier materials.The (SINIDUR) materials with nickel contents of 30 and 40 wt% are used in switching devices , requiring a higher arc erosion resistance and where increases in contact resistance can be compensated through higher contact forces.
The most important applications for Ag/Ni contact materials are typically in relays, wiring devices, appliance switches, thermostatic controls, auxiliary switches, and small contactors with nominal currents > 20A <xr id="tab:Application Examples and Forms of Supply for Silver-Nickel (SINIDUR) Materials"/><!--(Table 2.24)-->.
<figtable id="tab:Physical Properties of Silver-Nickel (SINIDUR) Materials">
<tr><th>Material/DODUCO</th><th>Silver Content</th><th>Density</th><th>Melting Point</th><th>ElectricalResistivity<i>p</i></th><th colspan="2">Electrical Resistivity (soft)</th></tr>
<tr>
<th>Designation</th><th>[wt%]</th><th>[g/cm<sup>3</sup>]</th><th>[°C]</th><th>[µΩ·cm]</th>
<th>[% IACS]</th><th>[MS/m]</th></tr>
<tr><td><p class="s11">Ag/Ni 90/10</p><p class="s11">SINIDUR 10</p></td><td><p class="s11">89 - 91</p></td><td><p class="s11">10.2 - 10.3</p></td><td><p class="s11">960</p></td><td><p class="s11">1.82 - 1.92</p></td><td><p class="s12">90 - 95</p></td><td><p class="s12">52 - 55</p></td></tr><tr><td><p class="s11">Ag/Ni 85/15</p><p class="s11">SINIDUR 15</p></td><td><p class="s11">84 - 86</p></td><td><p class="s11">10.1 - 10.2</p></td><td><p class="s11">960</p></td><td><p class="s11">1.89 - 2.0</p></td><td><p class="s12">86 - 91</p></td><td><p class="s12">50 - 53</p></td></tr><tr><td><p class="s11">Ag/Ni 80/20</p><p class="s11">SINIDUR 20</p></td><td><p class="s11">79 - 81</p></td><td><p class="s11">10.0 - 10.1</p></td><td><p class="s11">960</p></td><td><p class="s11">1.92 - 2.08</p></td><td><p class="s12">83 - 90</p></td><td><p class="s12">48 - 52</p></td></tr><tr><td><p class="s11">Ag/Ni 70/30</p><p class="s11">SINIDUR 30</p></td><td><p class="s11">69 - 71</p></td><td><p class="s11">9.8</p></td><td><p class="s11">960</p></td><td><p class="s11">2.44</p></td><td><p class="s12">71</p></td><td><p class="s12">41</p></td></tr><tr><td><p class="s11">Ag/Ni 60/40</p><p class="s11">SINIDUR 40</p></td><td><p class="s11">59 - 61</p></td><td><p class="s11">9.7</p></td><td><p class="s11">960</p></td><td><p class="s11">2.70</p></td><td><p class="s12">64</p></td><td><p class="s12">37</p></td></tr>
==== Silver-Metal Oxide Materials Ag/CdO, Ag/SnO<sub>2</sub>, Ag/ZnO====
The family of silver-metal oxide contact materials includes the material groups: silver-cadmium oxide, silver-tin oxide, and silverzinc oxide. Because of their very good contact and switching properties like high resistance against welding, low contact resistance, and high arc erosion resistance, silver-metal oxides have gained an outstanding position in a broad field of applications. They are mainly are used in low voltage electrical switching devices like relays, installation and distribution switches, appliances, industrial controls, motor controls, and protective devices <xr id="tab:Application Examples of Silver–Metal Oxide Materials"/><!--(Table 2.31)-->.
*'''Silver-cadmium oxide materials'''
