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arXiv · 1908.03785

Pressure-Thresholded Response in Cylindrically Shocked Cyclotrimethylene Trinitramine (RDX)

Leora E. Dresselhaus-Cooper·Dmitro Martynowych·Fan Zhang·Charlene Tsay·Jan Ilavsky·SuYin Grass Wang·Yu-Sheng Chen·Keith A. Nelson
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Abstract

We demonstrate a strongly thresholded response in cyclotrimethylene trinitramine (RDX) when it is cylindrically shocked using a novel waveguide geometry. Using ultrafast single-shot multi-frame imaging, we demonstrate that <100-{\mu}m diameter single crystals of RDX embedded in a polymer host deform along preferential planes for >100 ns after the shock first arrives in the crystal. We use in-situ imaging and time-resolved photoemission to demonstrate that short-lived chemistry occurs with complex deformation pathways. Using scanning electron microscopy and ultrasmall-angle X-ray scattering, we demonstrate that the shock-induced dynamics leave behind porous crystals, with pore shapes and sizes that change significantly with shock energy. A threshold pressure of ~ 12 GPa at the center of convergence separated the single-mode planar crystal deformations from the chemistry-coupled multi-plane dynamics at higher pressures. Our observations indicate preferential directions for deformation for our cylindrically shocked system, despite the applied stress along many different crystallographic planes.

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Leora E. Dresselhaus-Cooper, Dmitro Martynowych, Fan Zhang, Charlene Tsay, Jan Ilavsky, SuYin Grass Wang, Yu-Sheng Chen, Keith A. Nelson. 2019-08-10. Pressure-Thresholded Response in Cylindrically Shocked Cyclotrimethylene Trinitramine (RDX). https://doi.org/10.1021/acs.jpca.9b07637

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