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→Precious Metal Flakes
<tr><th><p class="s6">Preparation</p></th><th><p class="s6">Substrate</p><p class="s6">Material</p></th><th><p class="s6">Application by</p></th><th><p class="s6">Firing Temperature [°C]</p></th><th><p class="s6">Properties</p></th><th><p class="s6">Silver Content [wt%]</p></th></tr><tr><td><p class="s6">Argonor N92</p></td><td><p class="s6">glass, ceramics</p></td><td><p class="s6">paint brush, spray gun</p></td><td><p class="s6">530 - 650</p></td><td><p class="s6">Viscosity</p><p class="s6">500 – 1.000 mPa·s, good solderability</p></td><td><p class="s6">65</p></td></tr><tr><td><p class="s6">Argonor</p></td><td><p class="s6">glass,</p><p class="s6">ceramics</p></td><td><p class="s6">screen</p><p class="s6">printing</p></td><td><p class="s6">530 - 650</p></td><td><p class="s6">Viscosity</p><p class="s6">10 – 15.000 mPa·s, good solderability</p></td><td><p class="s6">65</p></td></tr></table>
</figtable>
=== Conductive Paints and Adhesives===
Conductive adhesives are used mostly for mechanical bonding with low thermal impact. As the adhesive components high-polymer organic substances such as epoxy resins and mixed polymers are mostly used. They are made of electrical filler materials such as flake shaped silver powders (70 – 80 wt%). Silver based conductive adhesives are available as single or two component adhesive systems. Both types are hardening without the application of pressure.
<figure id="fig:Flexible keyboard contact pattern printed with AUROMAL 170">
[[File:Flexible keyboard contact pattern printed with AUROMAL 170.jpg|left|thumb|Figure 3: Flexible keyboard contact pattern printed with AUROMAL 170]]
</figure>
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Conductive paints and adhesives have broad applications in electrical and electronic engineering. They are used for example for the contacting of film resistors, mounting of terminal wires, conducting electrostatic electricity or contacting components at low temperatures.
The mechanical strength of the bond connections depends mostly on the selected hardening temperature (<xr id="fig:Shear force of an adhesive joint"/> <!--(Fig. 8.4)-->).
<figure id="fig:Shear force of an adhesive joint">
[[File:Shear force of an adhesive joint.jpg|left|thumb|Figure 4: Shear force of an adhesive joint (silver adhesive AUROMAL K 20) as a function of the hardening temperature]]
</figure>
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=== Precious Metal Flakes===
To obtain certain desired physical properties of preparations, the dispersed precious metals in flat flake-like particles (generally called "flakes") are needed. These are produced by milling fine metal powders in the presence of milling additives or agents. The properties of these metal flakes, i.e. silver flakes (ability to disperse easily, flow characteristics, electrical conductivity) are strongly dependent on the particle shape and size as well as on the type of milling agents used. (<xr id="fig:SEM photos of silver flakes a fine grain b large flat"/><!--Fig. 8.5-->) illustrates through SEM photos a type of rather fine silver flake (medium particle size 4 – 6 µm) (a) and another one with relatively large flat but thin flake shapes (particle size 8 – 11 µm) (b). Typical commercial silver flake types are listed with their respective properties in (<xr id="tab:Typical Commercial Silver Flake Types"/><!--(Tab. 8.4)-->). Gold and platinum can also be produced as powder flakes. However, in terms of the quantities used, they are of lesser economic importance.
<figure id="fig:SEM photos of silver flakes a fine grain b large flat">
[[File:SEM photos of silver flakes a fine grain b large flat.jpg|left|thumb|Figure 5: SEM photos of silver flakes (a) fine grain (b) large flat]]
