Final Stage Solid State Sintering

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 ... 

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... 

Microstructure effects were studied in a series of Lao.825Sro,i75Mn03.5 polycrystalline samples prepared through a two-stage solid state reaction in air according to the procedure described in Refs. [21,24]. At the final stage of the samples preparation, the obtained products were sintered for 2 hours at = 1360 (pellet ), 1300 and 1200 °C (pellets B and C, respectively), and then furnace cooled down to room temperature. The details of the samples characterization and measurements were described elsewhere [21],... 

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