Analysis of Densification Process and Structure of PM Al-Mg-Si-Cu-Fe and Al-Zn-Mg-Cu-Sn Alloys

The paper is focused on the role of the pressing pressure on the densification behaviour of PM aluminium alloys. Commercially aluminium based powders Al-Mg-Si-Cu-Fe and Al-Zn-Mg-Cu-Sn were used as materials to be investigated. The apparent density of the powder mixes was determined according to MPIF St. 04. A set of cylinder test specimen 55X10X10 mm3 was uniaxially pressed in a floating hardened steel die. Compaction pressures ranged from 50 MPa up to 700 MPa. Considering the densification of metal powders in uniaxial compaction, quantification of aluminium compaction behaviour was performed. The compressibility behaviour was evaluated, considering the effect on specimens, as well as on their microstructure. The development of compressibility values with pressing pressure enables to characterize the effect of particles geometry and matrix plasticity on the compaction process.