Cylindrical Driven Shocks in Ceria
ORAL
Abstract
Shock compression of granular ceria was studied in converging cylindrical geometry using LANL Proton Radiography driven by the PHELIX magnetic implosion system in which a 1 mm thick liner-impactor was accelerated it to ~0.8 mm/$\mu s$. The impactor launched a shock in the cylindrical Al outer wall of the target assembly containing equiaxed, 63 $\mu$m-mean diameter ceria powder initially compacted to a static density of ~4 g/cc. The cylindrically converging shock in the ceria was observed with a series of 31 proton-radiographic frames down the axis of the cylinder. Results indicate that significant shock energy was expended in compacting the porous ceria, as the wave velocity markedly decreases during convergence, and a clear shock reflected from the axis was not observed. These observations are inconsistent with pre-shot modeling, and highlight the need for an improved understanding of the physics of compaction under non-ideal loading.
*This work was supported by the US Department of Energy through the Los Alamos National Laboratory. Los Alamos National Laboratory is operated by Triad National Security, LLC, for the National Nuclear Security Administration of U.S. Department of Energy (Contract No. 89233218CNA000001)
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