The Influence of Powder Mix on Densification and Compaction Mechanics in Uniaxial Cold Compaction

In previous work the relationships were determined which describe the densification of the powder column during uniaxial cold compaction and the stress field for the constitutive model. An improved processing method totally based on experimental data was defined. The present work exploits this improved experimental method to highlight the influence of material, investigating the behaviour of two commercial iron based powder mixes, which differ in chemical composition, alloying method, and apparent density. Densification is described by means of a new densification equation, based on the in-situ density and its correlation to the deformation experienced by the powder mix within the die cavity. The parameters in the power law equation allow to identify and compare the influence of the powder mix. The stress field acting on the powder column is investigated, and the relationships and parameters describing the constitutive model of the powder column are determined and compared for both materials.