Green microstructure, development

Consolidation is an important part of ceramic processing that consists in processes ranging from green body (i.e., not fired or sintered) forming to thermal consolidation (e.g., sintering). The consequences of the consolidation processes are densification and microstructure development of the ceramic body. 

In slip casting, initially, it is necessary to make up a suspension of the powder in a liquid and then, by a sort of filtration, a compact layer of the powder is deposited on the surface of a porous mould (Figure 5). The green microstructure in this case is basically developed as the liquid is... 

Nan and Weng (1999) have developed a Green function method to determine self-consistently the effective magnetostrictive properties of composites. The authors claim that their method, in principle, can be used to study the effects of material constants and microstructure, such as anisotropy, particle shape and orientation relative to the applied magnetic field. 

The development of the microstructure is strongly affected by the perfection of the Si green body. Inhomogeneities in density, pore size and distribution are... 

Surface area of a powder increases geometrically with decreasing particle size, so that the volume fraction of the outermost layer of ions on the surface increase significantly, which has a significant effect on properties of the powder. With the development of nanotechnology, it is readily to synthesize powders with nanosized particles (1-100 nm). Therefore, characterization of surface properties becomes more and more important. Specifically for ceramics or transparent ceramics, the consolidation of fine ceramic powders with liquid suspensions to produce more uniform green bodies has been shown to play an important role in the fabrication ceramics, especially when special or complex structures are required. Because the quality of microstructure of the consolidated body is determined by the dispersion behavior of the powder and the interaction between the particles in the suspension, which is closely related to the surface properties of the particles, controlling the physical and chemical properties of particles is a critical to ceramics fabrication. 

In this chapter we considered the common ceramic forming methods and briefly described the solid free-form fabrication routes applicable to ceramics. Powder consolidation forms the last major processing step prior to the sintering process in which the microstructure of the final article is developed. Heterogeneities present in the green body cannot be easily removed during sintering, so control of... 

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