Solid state sintering stages

Three stages of solid-state sintering are recognized, although there is not a clear distinction between them, and they overlap to some extent. 

W.S. Coblenz, J.M. Dynys, R.M. Cannon, and R.L. Coble. Initial stage solid-state sintering models A critical analysis and assessment. In G. C. Kuczynski, editor, Proceedings of the Fifth International Conference on Sintering and Related Phenomena, pages 141-157, New York, 1980. Plenum Press. 

Solid state sintering was discussed previously in this chapter. The sintering kinetics depend upon the rate determining step, which can be either viscous flow, grain boundary diffusion, or lattice diffusion. These sintering kinetics are summarized in Tables 16.4 and 16.6 for the initial and intermediate stage and Section 16.3.2.3 for the final stage. 

The rate-determining mechanism involved in initial as well as final stages of solid--state sintering is, according to current ideas, boundary or lattice diffusion of vacancies from sources at the boundary. The main arguments in favour of the diffusion mechanism are as follows ... 

Our approach to the firing stage will be to consider the physical principles of solid state sintering and then to consider how the sintering process is influenced by the key process variables, including the application of an external pressure and the presence of a liquid phase. 

Maximemko, A.L. and Olevsky, E.A. (2004) Effective diffusion coefficients in solid-state sintering, Acta Mater. 52, 2953. An example of the use of computer modeling to analyze the role of different diffusion processes in the various stages of sintering. 

Similar to the intermediate stage of solid-state sintering, the flux from the boundary per unit thickness is given by... 

In solid-state sintering, the processes of densification and grain growth (coarsening) are usually discussed separately. However, at the final stage of sintering, the two processes take place simultaneously with their rates have mutual influence. To fully... 

Koblenz, W. S., Dynys, J. M., Cannon, R. M. and Coble, R. L., Initial stage solid state sintering models. A critical analysis and assessment, in Sintering Processes, Mater. Sci. Res., Vol. 13, Plenum Press, New York, 141-57, 1980. 

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