Sintering viscous flow

Many different mechanisms have been proposed in the literature for the agglomeration of bed particles. Viscous flow sintering of liquid silicates, reactive liquid sintering of molten salt systems, chemical reaction sintering by formation of new compounds, solid state sintering and vaporisation followed by re-condensation have been reported by several investigators Chemical equilibrium models have... 

The implications for design are that the furnace exit gas temperature (that is the flue gas temperature leaving the radiant section) should be below the initial deformation temperature by about 50°C to avoid viscous flow sintering and potential slagging in the convection section. 

In viscous-flow sintering, some 20% of the initial solid melts at the sintering temperature and the densification of the material occurs by crystallisation of this phase (or vitrification if it becomes a glass) during cooling. Porcelains are prepared by this method. 

Ross JW, Miller WA, Weatherly GC (1981) Dynamic computer-simulation of viscous-flow sintering kinetics. J Appl Phys 52 3884—3888... 

In addition to solid state and liquid phase sintering, other types of sintering, for example, transient liquid phase sintering and viscous flow sintering, can be... 

Silica sinters by a viscous flow sintering mechanism while titania sinters by grain boundary diffusion. Kingery et al. (28) and Kobata et al. (29) have derived the... 

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