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→Fine-Grain Silver
Fine-Grain Silver (ARGODUR-Spezial) is defined as a silver alloy with an addition of 0.15 wt% of Nickel. Silver and nickel are not soluble in each other in solid form. In liquid silver only a small amount of nickel is soluble as the phase diagram ''(Fig. 2.51)'' illustrates. During solidification of the melt this nickel addition gets finely dispersed in the silver matrix and eliminates the pronounce coarse grain growth after prolonged influence of elevated temperatures ''(Figs. 2.49 and 2.50)''.
<xr id="fig:fig2.49"/> Fig. 2.49: Coarse grain micro structure of Ag 99.97 after 80% cold working and 1 hr annealing at 600°C[[File:Coarse grain micro structure of Ag.jpg|right|thumb|Coarse grain micro structure of Ag 99.97 after 80% cold working and 1 hr annealing at 600°C]]
<xr id="fig:fig2.50"/> Fig. 2.50: Fine grain microstructure of AgNi0.15 after 80% cold working and 1 hr annealing at 600°C <xr id="fig:fig2.51"/> Fig. 2.51: Phase diagram of silver-nickel <div class="multiple-images"> <figure id="fig:fig2.49">[[File:Coarse grain micro structure of Ag.jpg|left|thumb|<caption>Coarse grain micro structure of Ag 99.97 after 80% cold working and 1 hr annealing at 600°C</caption>]]</figure> <figure id="fig:fig2.50">[[File:Fine grain microstructure of AgNiO.jpg|rightleft|thumb|<caption>Fine grain microstructure of AgNi0.15 after 80% cold working and 1 hr annealing at 600°C</caption>]]</figure> <figure id="fig:fig2.51">[[File:Phase diagram of silver nickel.jpg|left|thumb|<caption>Phase diagram of silver nickel</caption>]]</figure></div><div class="clear"></div>
Fine-grain silver has almost the same chemical corrosion resistance as fine silver. Compared to pure silver it exhibits a slightly increased hardness and