Explosive compaction of tungsten powder using a converging underwater shock wave

Tungsten and tungsten-based alloys have wide applications in industries. Powder metallurgy is one of the major processes for production of tungsten parts, but tungsten parts with high density cannot be produced by this method. Two explosive compaction processes using converging underwater and no-water shock wave, were applied to compact tungsten powder in the present investigation. C4 as an explosive material with a detonation velocity of 8.2 km/s applied to consolidate amorphous powder with a mean grain size of 5 mu m. The density and hardness of consolidated tungsten parts were determined and by scanning electron microscope (SEM) analyzed their fragment surfaces. In addition to explosion experiments, a numerical simulation of compaction processes conducted by use of LS-DYNA program. Finally, the experimental results of two processes and numerical simulation results of the same processes compared. The results indicated that the tungsten parts without cracks and with a hardness equal to 570Vickers and a density equal to 18.5g/cm(3) can be obtained by underwater shock wave compaction method. (c) 2008 Elsevier B.V. All rights reserved.