Preparation of bulk nano-aluminum materials from nanopowder using explosive consolidation

To optimize powder explosive consolidation technology, an improved explosive consolidation device capable of relieving pressure was designed. Bulk nano-aluminum materials achieving more than 98% of standard density were successfully fabricated by explosive consolidation. The effect of different detonation velocities on the properties of the consolidated aluminum was investigated by varying the ratio of the ammonium nitrate explosive (AN-TNT) and wood flour to adjust the detonation velocity. The results revealed that the production of “Mach holes” (defects produced by excess energy in a converging shock wave) can be reduced by decreasing the detonation velocity. At a detonation velocity of 2158 m/s, bulk aluminum with high density, high hardness, high strength, and uniform microstructure without any Mach holes and with a grain size of about 80 nm can be achieved. The hardness of explosively consolidated aluminum was four times that of aluminum prepared by general industrial technology, and its compressive strength double that of industrially prepared aluminum.