Densification of Powder Compacts using a Unified Viscoplastic Constitutive Model

摘要

A model for densification of metallic powders isproposed. It involves viscoplastic constitutive equations basedon dislocation density evolution and also accounts for an effectof porosity. The model was applied to the case of cold powdercompaction under uniaxial compression conditions.Densification behaviour during powder compaction wassimulated using an explicit integration method as applied to thedislocation density evolution and the variation of the relativedensity of the compact. The model was gauged by comparingthe experimental data generated by cylindrical die compactiontests on Cu powder with the simulation results. The modelaccounts for the grain size and the deformation ratedependence of on the densification process.