Plastic behavior of agglomerated powder

The plastic properties of an agglomerated powder are investigated with the use of a material unit cell consisting of four agglomerates with a large pore between them. The contribution of the friction sliding of agglomerates and the existence of cohesionless contacts between agglomerates are taken into account in the modeling. The numerical results are obtained by utilizing a finite-element approach for the prediction of the rigid-plastic flow of the powder material. It is shown that the use of pressing with high level of shear stresses considerably reduces stresses necessary for consolidation. The analysis of the porosity evolution has confirmed that plastic deformation promoted the closure of large inter-agglomerate pores. The obtained results are important for better understanding of the consolidation of nano-powders.