The sintering behavior of ellipsoidal particles

Abstract

The sintering behavior of ellipsoidally shaped particles, particularly spheroids, was studied using a numerical kinetic Monte Carlo model for solid-state sintering. Compact packings of spheroids with five different aspect ratios from 0.5 to 2.0, thus comprising oblate, spherical, and prolate particles, were generated by simulating the pouring of such particles into a cubic container. For each spheroid particle aspect ratio, five different packings were generated to provide statistics on the sintering properties. The sintering behavior was quantified by the densification rate, relative density, anisotropic strain, grain size, and grain coordination number, as determined from the kinetic Monte Carlo model. The spherical particles were found to sinter to a relative density of 0.87 before grain growth occurs, whereas the oblate and prolate particles reach a relative density of 0.91 before grain growth sets in, with the prolate particles sintering slightly better compared to oblate particles. The more extreme the particle aspect ratio, the more anisotropic the strain is. Finally, the oblate and prolate spheroids have a slightly higher mean grain coordination number and a slightly higher initial relative density compared to the spherical particles.