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A study of the one-dimensional isentropic compression experiment (ICE), performed with High Explosive Pulsed Power (HEPP), has demonstrated that accurate, high stress, isentropic Equations of State (EOS) data may be obtained with this technique. The physics and accuracy of electromagnetic loading in the ICE technique are presented. It is shown that the HEPP-ICE load configuration is capable of producing magnetic stresses that are uniform to 1 part in 1000 over the central 87% of the sample faces, and that HEPP-ICE provides exact matching of the stresses between opposing samples. This magnetic uniformity, the exact matching, and the large sample sizes possible with HEPP-ICE, are necessary for the highest accuracy isentropic EOS data. The results for tungsten and copper demonstrate the inaccuracy of the technique, which may be as low as 0.2% in stress. [ABSTRACT FROM AUTHOR]

We are developing a prototype high explosive pulsed power (HEPP) system to obtain isentropic Equation of State (EOS) data with the Asay technique. Our prototype system comprises a flat-plate explosive driven magnetic flux compression generator (FCG), an explosively formed fuse (EFF) opening switch, and a series of explosively-actuated closing switches. The FCG is capable of producing ∼10 MA into suitable loads, and, at a length of 216 mm, the EFF will sustain voltages in excess of 200 kV. The load has an inductance of ∼3 to 10 nH, allowing up to ∼7 MA to be delivered in times of ∼0.5 μs. This prototype will produce isentropic compression profiles in excess of 2 Mbar in a material such as tungsten. We will obtain isentropic EOS data for copper at pressures up to ∼1.5 Mbar with the prototype system, immediately after this conference; eventually we plan to reach several tens of Mbar with larger, more advanced systems. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]