Study of compaction, preheating and strength in shock compressed porous silica

The shock response of porous silica is investigated using molecular dynamics. We develop Hugoniot curves of amorphous SiO₂as a function of initial preheat temperature for T = 300K to T = 600K and a range of porous states ranging from full density (2.2 g/cc) down to aerogel densities (0.22 g/cc). We focus on relatively low shock pressures (under 6.0 GPa) where the compaction state changes significantly in this regime. We show peak and residual shear stress plots as a function of pressure for this system. We find that the overall strength is dependent on the compaction state of the material, which is a function of both the initial temperature and initial porosity.

Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and 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-NA-0003525.