Shock-Wave Studies Of Ice Under Uniaxial Strain Conditions

Abstract

Shock-wave studies of ice under uniaxial strain conditions have been conducted at stress levels up to 3.6 GPa. A light-gas gun accelerated the flat-faced projectile used to impact the ice-containing targets. The ice samples were initially at ambient pressure and at temperatures of –10 ± 2° C. Gages were implaced at different distances in the ice along the path of the shock wave to measure particle velocity time histories inside the ice samples. The recorded time histories of particle velocity show a precursor wave with an average wave velocity of 3.7 km/s and an average particle velocity amplitude of 0.06 km/s. This wave is travelling at a wave velocity approximately 10% greater than longitudinal sound speed and is believed to originate because of the onset of melting of ice I.The particle velocity data from these experiments were converted to stresses and volumes using Lagrangian gage analysis and the assumption of a simple non-steady wave. This conversion provides a complete compression cycle (which includes both loading and unloading paths) for comparison with static measurements. All experiments show the onset of melting at 0.15 to 0.2 GPa. Experiments with maximum stress states between 0.2 and 0.5 GPa yield results which suggest that a mixed phase of ice I and liquid water exists at these conditions. For maximum loading stresses between 0.6 and 1.7 GPa the experimental results suggest that the final state is predominately ice VI. In these experiments the specific volume upon compression is changed from 1.09 m3/Mg to approximately 0.76 m3/Mg, which represents compaction of approximately 30%. The unloading paths determined from these experiments indicate that ice VI remains in a “frozen” or metastable state during most of the unloading process. This hysteresis in the compression cycle gives rise to a large “loss” of shock-wave energy to the transformation process. At stress levels above 2.2 GPa, ice VII should be the stable form for water according to static compression measurements. Experimental data at 2.4 and 3.6 GPa suggest that ice VII may be formed but these results indicate a mixed phase of ice VI and ice VII rather than complete transformation to ice VII.

In‐situ mass spectrometric observation of impact vaporization of water‐ice at low temperatures

“…This discrepancy between theoretical temperature and our values indicates that the impact energy is not deposited homogeneously, as assumed in the theoretical estimation, but is localized in a narrow region. Larson [1984] and Gaffhey [1985] estimated that the Hugoniot elastic limit (HEL) for water ice is 150-300…”

A New H2O Ice Hugoniot: Implications for Planetary Impact Events

“…2), were integrated to yield shock states (stress and volume) [4][5][6][7]. Target assemblies, consisting of 2 thermocouples and 3 or 4 electromagnetic particle velocity gauges embedded at 3-mm intervals between 50-mm diameter ice discs, were hung within a planar magnetic field and cooled by liquid nitrogen spray (Fig.…”

“…The combined ~150 K (this work) and ~250 K [13] shock data on 40-45 % porous ice (Fig. 5, inset) this work, [7], [12], [14], [15], [16]. Reproduced by permission of American Geophysical Union.…”

Thermodynamics of ice at high pressures and low temperatures

“…(1)) has been originally defined in the rectangular area O for pressures below 210 MPa. However, the experiments of Larson [12] indicate the presence of ice Ih in a shock-compressed non-equilibrium mixture of H 2 O phases at pressures up to 500 MPa; the shock-wave experiments of Stewart-Mukhopadhyay [14] on low-temperature ice show the incidence of ice Ih at even higher pressures. On the other hand, it has been observed [29] that the state-of-the-art multiparameter EOS yield the extrapolation behavior in regions not covered by data much better than usually expected.…”

“…The thermodynamics of ices and their equations-of-state (EOS) are of fundamental importance for many areas of science and technology, in particular, glaciology [6], oceanography [7], space and planetary science [8][9][10][11], physics of shock compression of water substance [12][13][14][15][16][17][18], high-pressure food processing [19][20][21][22][23] and low-temperature preservation of biological materials [24].…”