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This study was conducted in an attempt to develop a metallographic method for the investigation of pipe bombings. Three common pipe materials, ASTM A53 steel, AISI 304L stainless steel, and 6061-T6 aluminum, were shock-loaded using five high explosives and three propellants. The explosives used were ANFO, Composition C4, C6 detasheet, nitroglycerine-based dynamite, and flake TNT. The propellants used were FFFFg black powder. Red Dot smokeless powder, and Turbo Fuel A. The post-blast microstructure, hardness, and, in the case of 304L, transformed martensite content were examined for each test. The damage done to the microstructure was found to increase with increasing detonation velocity of the explosives and increase in pressure generated by the shock-metal interaction. Material hardness and, in the case of 304L, martensite content showed a sharp increase followed by a plateau as the shock pressure and detonation velocity increased.

The density dependence of the electronic energy band gap of the hydrogen has been studied with respect to the insulator-metal (IM) transition. The valence conduction band gap of solid hydrogen is about 15eV at zero pressure, therefore very high pressures are required to close the gap and achieve metallization. We propose to investigate what will be the degree to which one can expect to maintain a shockless compression of hydrogen with a low temperature (close to that of a cold isentrope) and verify if it is possible to achieve metallization. Multistage compression will be driven by energetic materials in a cylindrical implosion system, in which we expect a slow compression rate that will maintain the low temperature in the isentropic compression. It is hoped that pressures on the order of 100Mbars can be achieved while maintaining low temperatures. In order to better understand this multistage compression a smooth particle hydrodynamics (SPH) analysis has been performed. Since the SPH technique does not u...