Effect of Electromagnetic Force on the Strength of Electromagnetic Impulse Powder Compaction

This research aims to compact pure aluminum (Al) powder in a radial direction using the electromagnetic forming method. The pure Al powder was placed inside the Al tube and closed rigidly with end plugs. The Al tube used here acts as a force-transmitting medium to compact the powder using Lorentz forces and hold the powder intact. In this process, electromagnetic Lorentz forces were utilized to consolidate the powder. A copper solenoid coil with the help of a field shaper is used to generate the Lorentz forces. These forces were obtained when a high magnitude electrical current passes through the solenoid coil and its induced effect current in the adjacent tube. The radially acting magnetic field pressure deforms the Al tube; subsequently, the Al powder gets consolidated inside the tube. Thereby, a highly denser Al compact is obtained through a new technique. In this study, the effect of compaction voltage on various mechanical properties of the compact was studied. After successfully consolidating Al powder in the Al tube, the microstructures of the compacted samples were analyzed to characterize the porosity and distribution of powder particles using a scanning electron microscope and optical microscope results. The final diameter of the compressed samples was measured at several locations using Vernier callipers. Archimedes principle was used to determine the densities of the consolidated powder sample to ascertain the sintered density of the samples at various energies. Hardness tests were conducted on normal cross sections using Brinell hardness and Vickers hardness tester.