High-velocity compaction (HVC), an innovative approach to obtain green compacts with high and uniform density, is widely used in the powder metallurgy industry. In this study, meso force chains,...

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The densification of ferrous powder in high velocity compaction (HVC) is numerically captured by using discrete element method. Macro property (porosity), micro properties (coordination number (CN), radial distribution function (RDF) and unbalanced force), and meso properties (force chains and their orientations) are characterized and analyzed. The effect of force chains on the densification mechanism is studied. The densification in HVC is reciprocating in accordance with the evolution of local porosity and CN. This phenomenon can be promoted by the peak of unbalanced force. The number of peaks in RDF changes from three to four during densification. In addition, force chains evolve from top to bottom and then move in reverse. The distribution of force chains is related to the CN evolution, and the degree of densification is affected by the force chain strength. Force chains can promote densification by pushing particles and squeezing adjacent particles.

In this study, the friction mechanism and its relation to the force chains during powder compaction were analyzed by using the discrete element method. The results showed that the macroscopic frict...