Densification of Powders by Particle Deformation

TLDR

Based on prior experimental studies of particle deformation during powder compaction, the paper develops a model to describe the densification behavior of irregular packings of spherical particles. The study formulates a compaction equation that spans both stages of densification and applies it to non‑spherical powders to clarify how particle shape influences densification. The model employs the radial density function of a random dense packing to compute increases in average particle size and contact face number, uses a local yielding criterion to predict compaction pressure up to 90 % relative density, and represents final‑stage deformation as extrusion into remaining pore space. PM/0150.

Abstract

Based on a previous experimental study of particle deformation during powder compaction, a model is developed for describing the densification behaviour of an irregular packing of spherical particles. Using the radial density function of a ‘random dense packing’, the increase in both the average size and the number of contact faces are calculated. A simple criterion for local yielding allows the compaction pressure to be determined for relative densities up to 90%. In the final stage of compaction, particle deformation, now constrained by neighbouring contacts, is modelled by extrusion into the remaining pore space. A compaction equation encompassing both stages is presented; its application to non-spherical powders elucidates the role of particle shape during powder densification. PM/0150