Computer Modelling of Pore and Particle Shape Change during Compaction of Powder Materials in a Rigid Die using Finite Element Method

摘要

Presented is an application of finite element method for the analysis of pore and particle shape change during compaction of powder materials in a rigid die. The peculiarities of stress-strain state and density distribution within the volume of compacted powder material have been shown. Three different types of porous structures have been simulated with the help of representative cells: pores of spherical, square (different orientation), pentagonal shape. The influence of lubricant on compaction has been studied using different structures of representative cells as: without finite elements simulating lubricant between particles, with a lubricant material between particles with the amount of elements corresponds to the content of zinc stearate 0.5% and the borders between particles are filled with finite elements of lubricant simulating slip. Densification of powder composite materials has been determined using complicated representative cells consisted of hard and soft particles and pores of square shape. The content of hard and soft phases corresponds both percolating and segregative types of composites. Comparing the results of theoretical calculation of densification processes with experimental data showed satisfactory concurrence.