A reanalysis of the kinetics of neck growth during liquid phase sintering

Abstract

During liquid phase sintering, solid particles make contact and can subsequently coalesce into one particle. This coalescence phenomena can affect the type of microstructure formed and its subsequent coarsening behavior during liquid phase sintering. The mechanism of particle coalescence is assumed to be the liquid state analog of the evaporation-condensation mechanism of sintering. In this work, a detailed study of the geometry appropriate for analysis of the coalescence phenomena during liquid phase sintering is made. It is found that in the early stages of particle coalescence, the neck between the particles acts as a geometrical barrier to diffusion and the neck between the particles grows approximately ast ^1/5,i.e., the same kinetics appropriate for solid state sintering are obtained. At longer times, the neck area no longer restricts diffusive flow and at ^1/6 dependency of neck growth is obtained. The use of numerical techniques also allows the analysis to be carried out with fewer geometrical restrictions than in the original analysis of the evaporation-condensation mechanism.