Modeling the interaction between densification mechanisms in powder compaction

In this paper a micromechanical model of the interaction between densification mechanisms in powder compaction is presented. It accounts for elastic and power-law creep deformation of the bulk material along with stress-driven diffusion along the interparticle contact areas and curvature-driven diffusion on the pore surfaces. The finite element method is used to obtain the time-dependent deformation of the powder aggregate under plane strain deformation conditions. To reduce the number of case calculations needed to analyze the process, important dimensionless parameters that measure the relative magnitude of the densification mechanisms are identified. The calculated densification rates of the compact are compared with those predicted by analytical models, and conclusions are drawn on the significance of including the interaction between the densifying mechanisms in powder compaction models. (C) 2001 Elsevier Science Ltd. All rights reserved.