Experimental and numerical studies on electromagnetic axial powder compaction of Al 6061 powder

Abstract

In this work, the effect of discharge energy on the densification, mechanical properties, and microstructure of Al 6061 alloy compacted by electromagnetic axial compaction was studied. At 19 kJ, 22 kJ, and 25 kJ discharge energies Al 6061 powder was compacted. The aforementioned characteristics of Al 6061 compacts enhanced with discharge energy. Quantitatively, at the maximum discharge energy, relative density reached 96.7% and microhardness 44.78 VHN as well as compressive strength of 147.34 MPa. Optical microscopy results showed pores fraction decreases with increase in discharge energy with lowest porosity of 0.47%. At various time steps, LS-Dyna multi-physics modelling predicts powder body deformation, velocity, and stress-strain distribution which agreed well with experimental results. Significant visualisation by strongly coupled FEM-BEM showed that the top layer of the powder body deformed higher than the bottom layer according to displacement contours. Also, the thermal evolution of the driver plate can be successfully captured.