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Title: Isentropic Compression Experiments Performed By LLNL On Energetic Material Samples Using The Z Accelerator

Abstract

Several experiments have been conducted by LLNL researchers using isentropic compression experiments (ICE) on energetic materials as samples from Fiscal Year 2001 (FY01) to Fiscal Year 2005 (FY05). Over this span of time, advancements of the experimental techniques and modeling of the results have evolved to produce improved results. This report documents the experiments that have been performed, provides details of the results generated, and modeling and analysis advances to fully understand the results. Publications on the topics by the various principal investigators (PI's) are detailed in the Appendices for quick reference for the work as it progressed.

Authors:
; ; ; ; ; ; ; ;
Publication Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
923106
Report Number(s):
UCRL-TR-236063
TRN: US0802207
DOE Contract Number:
W-7405-ENG-48
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 42 ENGINEERING; ACCELERATORS; COMPRESSION; LAWRENCE LIVERMORE NATIONAL LABORATORY; SIMULATION

Citation Formats

Vandersall, K S, Reisman, D B, Forbes, J W, Hare, D E, Garcia, F, Uphaus, T M, Elsholz, A J, Tarver, C M, and Eggert, J H. Isentropic Compression Experiments Performed By LLNL On Energetic Material Samples Using The Z Accelerator. United States: N. p., 2007. Web. doi:10.2172/923106.
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Vandersall, K S, Reisman, D B, Forbes, J W, Hare, D E, Garcia, F, Uphaus, T M, Elsholz, A J, Tarver, C M, & Eggert, J H. Isentropic Compression Experiments Performed By LLNL On Energetic Material Samples Using The Z Accelerator. United States. doi:10.2172/923106.
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Vandersall, K S, Reisman, D B, Forbes, J W, Hare, D E, Garcia, F, Uphaus, T M, Elsholz, A J, Tarver, C M, and Eggert, J H. Thu . "Isentropic Compression Experiments Performed By LLNL On Energetic Material Samples Using The Z Accelerator". United States. doi:10.2172/923106. https://www.osti.gov/servlets/purl/923106.
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@article{osti_923106,
title = {Isentropic Compression Experiments Performed By LLNL On Energetic Material Samples Using The Z Accelerator},
author = {Vandersall, K S and Reisman, D B and Forbes, J W and Hare, D E and Garcia, F and Uphaus, T M and Elsholz, A J and Tarver, C M and Eggert, J H},
abstractNote = {Several experiments have been conducted by LLNL researchers using isentropic compression experiments (ICE) on energetic materials as samples from Fiscal Year 2001 (FY01) to Fiscal Year 2005 (FY05). Over this span of time, advancements of the experimental techniques and modeling of the results have evolved to produce improved results. This report documents the experiments that have been performed, provides details of the results generated, and modeling and analysis advances to fully understand the results. Publications on the topics by the various principal investigators (PI's) are detailed in the Appendices for quick reference for the work as it progressed.},
doi = {10.2172/923106},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Thu Oct 25 00:00:00 EDT 2007},
month = {Thu Oct 25 00:00:00 EDT 2007}
}
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Technical Report:
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DOI:  10.2172/923106
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    Recently an innovative technique known as the Isentropic Compression Experiment (ICE) was developed that allows the dynamic compressibility curve of a material to be measured in a single experiment. Hence, ICE significantly reduces the cost and time required for generating and validating theoretical models of dynamic material response. ICE has been successfully demonstrated on several materials using the 20 MA Z accelerator, resulting in a large demand for its use. The present project has demonstrated its use on another accelerator, Saturn. In the course of this study, Saturn was tailored to produce a satisfactory drive time structure, and instrumented tomore » produce velocity data. Pressure limits are observed to be approximately 10-15 GPa (''LP'' configuration) or 40-50 GPa (''HP'' configuration), depending on sample material. Drive reproducibility (panel to panel within a shot and between shots) is adequate for useful experimentation, but alignment fixturing problems make it difficult to achieve the same precision as is possible at Z. Other highlights included the useful comparison of slightly different PZT and ALOX compositions (neutron generator materials), temperature measurement using optical pyrometry, and the development of a new technique for preheating samples. 28 ICE tests have been conducted at Saturn to date, including the experiments described herein.« less

  • ; ; ; ...
    Isentropic compression experiments and numerical simulations on TATB based HE were performed respectively at Z accelerator facility from Sandia National Laboratory and at Lawrence Livermore National Laboratory in order to study the isentrope and associated Hugoniot of this HE [1]. 3D configurations have been calculated here to test the new beta version of the electromagnetism package coupled with the dynamics in Ls-Dyna and compared with the ICE Z shot 1967.

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  • This paper provides a brief review of experimental techniques for producing dynamic isentropic compression of samples to pressures of several hundred GPa. Traditional gun launch techniques include use of buffer plates, such as fused silica, that exhibit negative curvature to their stress-strain response and graded-density impactors. Graded-density impactors have been used to study isentropic compression of specimens to pressures exceeding 2 Mbar on high-impedance materials. A recent development includes the use of the Sandia Z Accelerator to produce magnetic compression in planar specimens to pressures of a few hundred kbar over time scales of 100 ns. These techniques have beenmore » successfully applied to isentropic compression of iron to 300 kbar and copper to 130 kbar. The iron results indicate that it is possible to study the polymorphic phase change that occurs at 130 kbar and also the kinetic properties of the transformation. The copper results indicate that with further improvements in progress it should be possible to measure continuous isentropic compression curves in materials of interest to pressures exceeding 1 Mbar. The Z accelerator is limited to peak currents of about 20 MA. By reconfiguring the anode-cathode geometry it should be possible to obtain constant current density and thus driving pressure to about 3 Mbar. The next generation accelerator referred to as ZX, which is being proposed will have the capability to generate currents to 50 MA and resulting peak pressures to 15 Mbar.« less

  • - Physics of Plasmas
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