Theory of Sintering

V.V. Skorohod, Development of the ideas of Ya. I. Frenkel in the contemporary rheological theory of sintering, Powder Metall. Metal Ceram., 34, 521-527 (1995). 

Olevsky EA (1998) Theory of sintering from discrete to continuum. Mater Sci Eng R-Rep 23 41-100... 

The shrinkage rate due to power-law creep, 8creep can be evaluated based on the continuum theory of sintering, which deals with the dependences of normalized shear and bulk viscosity modules on porosity, 9, along with the effective sintering. 

A comprehensive theory of sintering should be capable of describing the entire sintering process as well as the evolution of the microstructure (i.e., grain size, pore size, and the distribution of the grain and pore sizes). However, in view of the complex nature of the process, it is unlikely that such a theory will be developed. A more realistic approach, which is adopted in this book, is to first develop an understanding of the densification and coarsening phenomena separately and then explore the consequences of their interaction. 

Figure 11.20 Comparison of the predictions of Scherer s theory of sintering with rigid inclusions with the predictions of the rule of mixtures. The linear strain rate of the composite normalized by the strain rate from the rule of mixtures [Eq. (11.7)] is plotted versus the relative density of the matrix for the indicated volume fraction of inclusions Vf. The dashed curves represent the composite sphere model [Eq. (11.33)], and solid curves, the self-consistent model [Eq. (11.35)]. (From Ref. 33.)...

In this section brief description of the theory of sintering and the advantage of sol-gel prepared powders as starting materials are presented. The following sections will be devoted to the representation of sintered ceramics obtained by the sol-gel prepared precursors. 

Theory of Sintering of Crystalline Materials describes models based on transport by diffusion. The low initial density of gels and the strong tendency toward grain growth make it difficult to sinter to full density. 

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