New high-pressure shock-wave data have been obtained for W and Mo. These data have been combined with previous data sets for these materials to extend the range of linear us–up fits for the Hugoniot to 480 GPa for Mo and 680 GPa for W. The shock-wave data, supplemented by the necessary thermodynamic information, have been used to generate several isotherms (100, 200,...1000 K). Tables of pressure versus relative volume up to 380 GPa suitable for comparison with statically obtained data are given.

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A definitive set of the Los Alamos Hugoniot data for iron in a pressure regime extending to 442 GPa is given. Earlier standards data, obtained using conventional explosive systems, were thoroughly reprocessed. All original film records were reread. On the basis of more recent experiment and theory, some data were culled because the experimental designs were found to be insufficiently conservative. The analysis was also modified to take into account preheating of the explosively driven flyer plates. Minor clerical errors in transcription of measurements were corrected. An improved algorithm for the flash-gap time correction was incorporated. Higher-pressure data were obtained using a conventional 13-pin target assembly on a two-stage light gas gun. Several polynomial representations of the data are given. A linear fit to the data (Us=3.935+1.578 Up, where the shock velocity Us and the particle velocity Up are in km/s) has a root-mean-square misfit of 62 m/s. The quadratic fit (Us=3.691+1.788 Up−0.038 Up2) has a root-mean-square misfit of 39 m/s.

We present experimental results supporting physics-based ejecta model development, where our main assumption is that ejecta form as a special limiting case of a Richtmyer–Meshkov (RM) instability at a metal–vacuum interface. From this assumption, we test established theory of unstable spike and bubble growth rates, rates that link to the wavelength and amplitudes of surface perturbations. We evaluate the rate theory through novel application of modern laser Doppler velocimetry (LDV) techniques, where we coincidentally measure bubble and spike velocities from explosively shocked solid and liquid metals with a single LDV probe. We also explore the relationship of ejecta formation from a solid material to the plastic flow stress it experiences at high-strain rates ($1{0}^{7} ~{\mathrm{s} }^{\ensuremath{-} 1} $) and high strains (700 %) as the fundamental link to the onset of ejecta formation. Our experimental observations allow us to approximate the strength of Cu at high strains and strain rates, revealing a unique diagnostic method for use at these extreme conditions.

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