Correlation mechanism between force chains and friction mechanism during powder compaction

Abstract

The relation between friction mechanism and force chains characteristics has not yet been fully studied in the powder metallurgy research area. In this work, a uniaxial compression discrete element model is established based on the compaction process of ferrous powder. Furthermore, the correlation mechanism between force chains and the friction mechanism during powder compaction is investigated. The simulation results reveal a strong correlation between the variation of the friction coefficient and the evolution of force chains. During the powder compaction, the friction coefficient would eventually tend to be stable, a feature which is also closely related to the slip ratio between particles. The side wall friction and the friction between particles would have an important effect on the direction of force chain growth in about one-third of the area near the side wall. The research results provide theoretical guidance for improving the densification process of the powder according to the force chain and friction.