Green density analysis on the process of 10% Cu-Sn powder compaction in development of frangible bullet

One of the developments in the frangible bullet in Indonesia is carried out by a workshop at the Department of Material Engineering, ITS. The product is produced by mixing, compaction and sintering of 10% Cu-Sn powder. One drawback is that the bullets begin to deform (or even disintegrate) when they are put into the cartridge case. It is suspected that the heterogeneity of the bullet density after going through the powder compacting process is the main cause. In this study, the discrete element method was used to predict the density distribution in the compaction process. The pressure is varied from 500, 700, and 900 Psi. Two types of frangible bullet geometries were introduced, namely, flat nose and full round. The bulk relative density distribution of frangible bullet was then calculated. There are repeating patterns for all variations. Areas close to a pressure source have a higher density than areas far away. This pattern indicates that the density is not fairly uniform. The lowest density of 1614.21kg/m3 occurs at a pressure of 500 Psi for a full round nose bullet, and the highest is 1952.608kg/m3 at a pressure of 900 Psi at the same bullet geometry. It can be concluded that there is a heterogeneous density after the compaction process, but relatively small. The resulting green density is still below the required density of frangible bullets.