Results of Rayleigh-Taylor material strength experiments at high pressure and high strain rates on NIF and Omega

We are studying material strength at high pressures (upto 8 Mbar), high strain rates (~10⁷ s^-1) and high strains (> 30%) under ramped compression condition using Rayleigh-Taylor instability properties. Understanding plastic deformation dynamics of materials under these extreme conditions is an area of research of high interest to a number of fields, including meteor impact dynamics and advanced inertial confinement fusion designs. We have studied various metals such as tantalum, lead and copper using laser driven high pressure platform. Our studies show that the work hardening dominates in this regime. We will describe the experimental results of the high pressure, high rate plastic deformation dynamics of various metals from Omega and NIF in comparison with the various strength models including Livermore Multiscale Model [2].

[1] H. –S. Park et al., Phys. Rev. Lett. 114, 065502 (2015).
[2] N. Barton, et al., J. App. Physics, 109, 073501 (2011).