Computational and Experimental Study of TATB Shock Initiation at the Grain Scale

Shock initiation of high explosives is believed to be controlled by hot spots that ignite, grow, and coalesce. We designed shockwave experiments (Nov. 2017) to directly measure the early stages of shock initiation with spatial resolution of several microns. Supporting simulations have been conducted to optimize the experimental design and help interpret the experimental data. The first stage of this work is to characterize the grain structure in TATB plastic-bonded samples that are 0.12 - 0.20 mm thick. We used computed tomography capabilities to examine the 3D particle structures. Further, we will investigate the response of these samples to shock waves at the 0.010 - 0.10 mm scale. Experiments will be conducted at LLNL’s Jupiter Laser Facility. Line-VISAR measurements of shocks will determine time dependent flow velocities with an appropriate spatiotemporal resolution to capture variations induced by the grain-scale structure of the materials. Microwave transmission/reflection measurements will be simultaneously conducted to characterize void collapse and ignition phenomena.

Lawrence Livermore National Laboratory is operated by Lawrence Livermore National Security, LLC, for the U.S. Department of Energy, National Nuclear Security Administration under Contract DE-AC52-07NA27344.