Rheology, packing and sintering behavior in dense suspension of multimodal spherical silica

Abstract

Pursuing the limit of solid volume fraction of suspension and packing density of compacts is an important issue in industry such as ceramic processing. In present manuscript, the experiment results show that a very high solid volume content (82%) in suspension and a high packing density (92%) of compacts can be obtained, by using spherical particles to optimize particle size distribution. The proposed model can well predict the maximum solid fraction of mixtures at a given volume fraction of smaller particles. The correlation between viscosity and solid volume fraction could be expressed by an exponential equation. About the green bodies prepared from suspensions, the green density has important influence on sintered body density especially on the initial sintering stage. And dense sintered body with amorphous phase could be obtained at sintering temperature of 1100 °C.