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→Silver-Nickel (SINIDUR) Materials
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:tab2.24"/> (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:tab2.23"/> (Table 2.23).
Typically Ag/Ni (SINIDUR) materials are usually produced with contents of 10-40 wt% Ni. The most widely 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:fig2.72Softening of AgNi9010 after annealing"/> (Fig. 2.72) <xr id="fig:fig2.73Strain hardening of AgNi8020"/> (Fig. 2.73) <xr id="fig:fig2.74Softening 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 increasesin 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, auxiliaryswitches, and small contactors with nominal currents >20A <xr id="tab:tab2.24"/> (Table 2.24).
<figtable id="tab:Physical Properties of Silver-Nickel (SINIDUR) Materials">
<xr id="fig:Strain hardening of AgNi9010 by cold working"/> Fig. 2.71: Strain hardening of Ag/Ni 90/10 by cold working
<xr id="fig:fig2.72Softening of AgNi9010 after annealing"/> Fig. 2.72: Softening of Ag/Ni 90/10 after annealing for 1 hr after 80% cold working
<xr id="fig:fig2.73Strain hardening of AgNi8020"/> Fig. 2.73: Strain hardening of Ag/Ni 80/20 by cold working
<xr id="fig:fig2.74Softening of AgNi8020 after annealing"/> Fig. 2.74: Softening of Ag/Ni 80/20 after annealing for 1 hr after 80% cold working
<xr id="fig:fig2.75"/> Fig. 2.75: Micro structure of Ag/Ni 90/10 a) perpendicular to the extrusion direction b) parallel to the extrusion direction
</figure>
<figure id="fig:fig2.72Softening of AgNi9010 after annealing">
[[File:Softening of AgNi9010 after annealing.jpg|right|thumb|<caption>Softening of Ag/Ni 90/10 after annealing for 1 hr after 80% cold working</caption>]]
</figure>
<figure id="fig:fig2.73Strain hardening of AgNi8020">
[[File:Strain hardening of AgNi8020.jpg|right|thumb|<caption>Strain hardening of Ag/Ni 80/20 by cold working</caption>]]
</figure>
<figure id="fig:fig2.74Softening of AgNi8020 after annealing">
[[File:Softening of AgNi8020 after annealing.jpg|right|thumb|<caption>Softening of Ag/Ni 80/20 after annealing for 1 hr after 80% cold working</caption>]]
</figure>