Sintering kinetics at final stage sintering: model calculation and map construction Original Research Article

Ever since the development of a late stage sintering model by Coble in 1961, densification at the final stage of solid state sintering has been explained basically by Cobleʹs model for lattice diffusion. For grain boundary diffusion, equations based on Herringʹs scaling law were later developed and utilized. The present paper examines previous sintering models, in particular, Cobleʹs sintering model, and presents a new diffusion model and kinetic equations. The new model accounts for the role of grain boundaries and the diffusion area in densification in contrast to Cobleʹs model. Sintering kinetics have been calculated and the relative contributions of lattice and grain boundary diffusion evaluated. It has been shown that the densification mechanism can vary with pore size change during sintering, unlike the conclusions of previous investigations. The results have been highlighted as a sintering diagram.