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

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-μm 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 is linked to high-energy deformation planes. Using scanning electron microscopy and ultrasmall-angle X-ray scattering, we demonstrate that the shock-induced dynamics leave behind sintered 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 deformation mechanics in our cylindrically shocked system, despite the applied stress along many different crystallographic planes. AUTHOR INFORMATIONCorresponding Author: Leora E. Dresselhaus-Cooper, dresselhausc1@llnl.gov † Present address: Author ContributionsThe project was directed by KAN. Shock experiments were carried out by LEDC. Samples were prepared by LEDC and DJM. USAXS experiments were performed with LEDC, FZ, JI and DJM. The orientation of the crystal in Fig. 6 was measured by LEDC, CT, SYGW and YSC.Analysis of the results were carried out by LEDC and KAN. The manuscript was written by LEDC, with supporting contributions from all authors.

Investigation of temperature effect on pressure measurement using Raman peak shift by variable temperature and pressure Raman experiment

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Selective Phonon Stimulation Mechanism to Tune Thermal Transport

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