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In the ceramic technology, packing models are very importantly for correlation the structural properties of powders, green bodies and sintered bodies . In this paper we have studied some structural and dimensional properties of Y2O3 low doped nano α -Al2O3 powders in correlation with the green bodies and sintered compacts fractures, in point of the mathematical concepts: porosity, coefficient of porosity, packing modelling defined in quantified abstract space and real space R3.
The characterisation ans study of nano-powder materials used for the preparation of green bodies and sintered compacts is one of the basic conditions for realisation an optimal / economical technology. The shape, the average particle size, the distribution of the particles determines the characteristics of sintered material compacts, such as structure and electro-mechanical characteristics. The physical – chemical state of the row materials (initial nano powders) is a complex criterion, very important, both the technological and theoretical studies, for the characterization of the powders in point of : grinding, pressing, sintering etc.
We have studied: the packing models for the followings particle shapes, observed in the low Y doped nano α -Al2O3 (powders and fracture): elliptical-cylindrical, ellipsoidal-cylindrical, and spherical cylindrical, circular-cylindrical, and hexagonal-prismatic.
The row materials (powders) and sintered samples (fracture) were investigated by scanning electron microscopy (SEM) and transmission electron microscopy (TSM) We have determined the grain size distributions, the shape (geometry) of the grains and the porosity in the fracture . All parameters were correlated with the geometric parameters of the powders - shape, distribution of the size.
The paper established the equations by which is possible to forecast the final porosity (with a good probability) from the powder - green bodies phases before the sintered bodies realisation (with a big energy economy).
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