Dynamic Model of Compaction Process of Metallic Powders

Dynamic modeling of compaction process ,and evaluation of hardening parameters of powder compacts undergoing uni-axial/multi compaction is a tedious process and requires many elaborate tests .However ,assuming a two-parameter failure surface ( such as Mohr–Coulomb),evolution of failure surface may be monitored by two points on the failure surface. Results of uni-axial compression and direct or indirect tensile tests may readily provide the two required points. In order to assess this hypothesis ,a laboratory investigation was carried out using atomized iron powder(WPL-200) and aluminum powder(+160Mm) . Green compacts of the said drop-hammer , specifically designed for this purpose. Specimens with various relative compactions were produced and tested in uni-axial compression test and Brazilian split test .Variations of compressive/tensile strength with compaction energy(hammer speed) and relative density were studied and hardening law for green compacts were developed.