Grain size reduction influence

Empirically based equations for calculating the reduction time and average particle size have been derived for rotary fiimaces [5.73] but have never been applied industrially. The main difficulty is that the properties of the raw material play a crucial role in the reduction process, and these characteristics are not well enough represented by corresponding equations. This is partieularly true for smaller grain sizes. For larger grain sizes, the influence of the oxide precursor is less pronounced. 

Tellurium and cadmium Electrodeposition of Te has been reported [33] in basic chloroaluminates the element is formed from the [TeCl ] complex in one four-electron reduction step, furthermore, metallic Te can be reduced to Te species. Electrodeposition of the element on glassy carbon involves three-dimensional nucleation. A systematic study of the electrodeposition in different ionic liquids would be of interest because - as with InSb - a defined codeposition with cadmium could produce the direct semiconductor CdTe. Although this semiconductor can be deposited from aqueous solutions in a layer-by-layer process [34], variation of the temperature over a wide range would be interesting since the grain sizes and the kinetics of the reaction would be influenced. 

In industrial practice, the choice of proper reduction parameters is based exclusively on empirical experience. Besides the average grain size, the reduction parameters also influence the grain size distribution, agglomeration, apparent density, and grain morphology-... 

SLS processes are more complex than most other RP-technologies. Because of its pressureless characteristic, the only driving force for densification of powder is a reduction in total surface area [96]. So there is a high influence of the initial density of the powder layer on the resulting part density and contour accuracy depending on the properties of the used powder materials, for example grain size distribution. Therefore, surface properties are not quite as good as with SLA. 

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