Shock-ramp compression of tin using thin-film graded-density impactors

Graded-density impactors have long been recognized as a technology capable of producing off-Hugoniot compression from a plate impact, but there remain challenges in manufacturing smooth and spatially uniform gradings that enable high fidelity dynamic material property measurements. In this work, a novel sputter deposition technique was used to produce a continuous grade in material composition from aluminum to gold over an impactor thickness of ~40mm. The density gradient was tailored specifically for compression of thin (~60mm) tin samples resulting in a shock-ramp compression path over timescales of ~10ns. The impactors were launched with a 2-stage gun to velocities of 3-6 km/s which results in a variety of interesting trajectories through the phase space of tin including solid, liquid, and mixed solid-liquid phases. The experiments were diagnosed with PDV and wave profile analyses give estimates for the compressibility and strength.

Sandia National Laboratories is a multimission laboratory managed and operated by National Technology & Engineering Solutions of Sandia, LLC, a wholly owned subsidiary of Honeywell International Inc., for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA0003525. This work describes objective technical results and analysis. Any subjective views or opinions that might be expressed in the work do not necessarily represent the views of the U.S. Department of Energy or the United States Government.