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:'''a) Powder blending from single component powders''' <br> In this common process all components including additives that are part of the powder mix are blended as single powders. The blending is usually performed in the dry stage in blenders of different design.
:'''b) Powder blending on the basis of doped powders''' <br> For incorporation of additive oxides in the SnO2 powder the reactive sprayprocess (RSV) has shown advantages. This process starts with a waterbased solution of the tin and other metal compounds. This solution is nebulized under high pressure and temperature in a reactor chamber. Through the rapid evaporation of the water each small droplet is convertedinto a salt crystal and from there by oxidation into a tin oxide particle in which the additive metals are distributed evenly as oxides. The so created doped AgSnO2 powder is then mechanically mixed with silver powder.
:'''c) Powder blending based on coated oxide powders''' <br> In this process tin oxide powder is blended with lower meting additive oxidessuch as for example Ag2 MoO4 and then heat treated. The SnO2 particles are coated in this step with a thin layer of the additive oxide.
:'''d) Powder blending based on internally oxidized alloy powders''' <br> A combination of powder metallurgy and internal oxidation this process starts with atomized Ag alloy powder which is subsequently oxidized in pure oxygen. During this process the Sn and other metal components are transformed to metal oxide and precipitated inside the silver matrix of each powder particle.
:'''e) Powder blending based on chemically precipitated compound powders''' <br> A silver salt solution is added to a suspension of for example SnO2 together with a precipitation agent. In a chemical reaction silver and silver oxiderespectively are precipitated around the additive metal oxide particles whoact as crystallization sites. Further chemical treatment then reduces the silveroxide with the resulting precipitated powder being a mix of Ag and SnO2.
