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→Silver-Palladium Alloys
====Silver-Palladium Alloys====
The addition of 30 wt% Pd increases the mechanical properties as well as the resistance of silver against the influence of sulfur and sulfur containingcompounds significantly <xr id="tab:tab2.17Physical Properties of Silver-Palladium Alloys"/> (Tab 2.17) and <xr id="tab:tab2.18Mechanical Properties of Silver-Palladium Alloys"/> (Tab.2.18). Alloys with 40-60 wt% Pd have an even higher resistance against silver sulfide formation. At these percentage ranges however the catalytic properties of palladium can influence the contact resistance behavior negatively. The formability also decreases with increasing Pd contents.
AgPd alloys are hard, arc erosion resistant, and have a lower tendency towards material transfer under DC loads <xr id="tab:tab2.19Contact and Switching Properties of Silver-Palladium Alloys"/> (Table 2.19). On the other hand the electrical conductivity is decreased at higher Pd contents. The ternary alloy AgPd30Cu5 has an even higher hardness which makes it suitable for use in sliding contact systems.
AgPd alloys are mostly used in relays for the switching of medium to higher loads (>60V, >2A) as shown in <xr id="tab:tab2.20Application Examples and Forms of Suppl for Silver-Palladium Alloys"/> (Table 2.20). Because of the high palladium price these formerly solid contacts have been widely replaced by multi-layer designs such as AgNi0.15 or AgNi10 with a thin Au surface layer. A broader field of application for AgPd alloys remains in the wear resistant sliding contact systems.
<figtable id="tab:tab2.17Physical Properties of Silver-Palladium Alloys">
'''Table 2.17: Physical Properties of Silver-Palladium Alloys'''
<figtable id="tab:tab2.18Mechanical Properties of Silver-Palladium Alloys">
'''Table 2.18: Mechanical Properties of Silver-Palladium Alloys'''
<table class="twocolortable">
<figtable id="tab:tab2.19Contact and Switching Properties of Silver-Palladium Alloys">
'''Table 2.19: Contact and Switching Properties of Silver-Palladium Alloys'''
<figtable id="tab:tab2.20Application Examples and Forms of Suppl for Silver-Palladium Alloys">
'''Table 2.20: Application Examples and Forms of Suppl for Silver-Palladium Alloys'''
<table class="twocolortable">