The authors of [1][2][3] established that there is transformation of water into a solid phase (ice VII) under shock compression. It was shown that the shock adiabat of water splits into three separate parts (Figs. 1 and 2). In particular, in the coordinates wave velocity D vs. mass velocity u, these parts are rectilinear sections ( Fig. 1) with their values of the coefficients Co and X in the equation(1) The lower 1 and upper 3 sections are interpreted as corresponding to the liquid phase, and the intermediate 2 as corresponding to a mixture of the liquid phase and ice VII. To estimate temperatures two types of equation of state are used: the Mie--Gruneisen equation and the Zamyshlyayev-Menzhulin interpolation equation [4]. In the Mie--Gruneisen equationthe following expressions derived in [5] are used for the cold constituent of both the pressure Pc and the internal energy EcHere P is the pressure; E is the internal energy; T is the temperature; Cv is the specific heat; F is the Gruneisen parameter; p is the density; Ap = p -P0; the subscript 0 refers to the initial state under normal conditions; subscript c to cold constituents, and T to thermal constituents. The convenience of expressions (3) is that they contain the coefficients Co and A entering into linear relation (1) between the wave and mass velocities. The latter are presented in tables for a large number of materials [6,7], or can be calculated following the rules in [8,9]. The shock adiabat of ice-VII is obtained by processing of the experimental results of [10] on the isothermal compressibility of ice VII (T = 298 K and P = 3-8 GPa). The data of [10] are described by the Mie--Gruneisen equation with the cold constituent in the form of (3). As a result, the coefficients in linear relation (1) between the kinematic parameters of ice VII were evaluated as C0vll = 3.067 km/sec and A = 1.968, and the initial density of ice VII P0vII = 1.5198 9 10 a kg/m 3. It should be noted that this value is close to the density of ice VII p = 1.5-103 kg/m 3 given by Eisenberg and Kauzman [11] without specifying other parameters of state. Olinger and Halleck [10] obtained the value V0 = 1/po = (0.696-0.731)-10 -3 ma/kg and called it the ambient specific volume.Further the mass fractions of the components (Fig. 3) are evaluated from known shock adiabats of both the mixture at section 2 and its components using the rule of additivity proved experimentally in [12,13]. It is found that the shock adiabat of water in the temperature-pressure plane intersects twice the curve of liquid-ice VII phase equilibrium and is in the region of ice VII in the pressure range from 2.86 to 10.1 GPa. In this region the mass portion of ice VII increases from 0.8 at the lowest point to 27% at the highest point. The existence of a solid phase in shock-compressed water in the above pressure range was substantiated in [1][2][3] by the known data of other authors who studied properties of shock-compressed water such as viscosity [14], compressibility [15], and freezing [16].'However, the details o...

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Experimental techniques to study shocked substances are described. They include specimen loading by an oblique damping shock wave and impulsivex-raying. The method makes it possible to obtain a dynamical picture with an oblique shock wave, a moving free surface, the back boundary of a spall layer, and so on. The values of parameters and spall damage may then be calculated.