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An approximation of equation of state for matter is treated, which involves the consistent use of interpolation approach with respect to both density and temperature in the entire nonrelativistic region. The cold component is defined under normal conditions by four experimentally obtained parameters, namely, specific volume, bond energy, bulk modulus, and parameter κ = -(∂lnB S /∂lnV) S . The thermal ion component describes the transition from lattice vibrations with free Debye energy as a function of characteristic temperature being introduced, which makes possible the extension of the range of its application from zero temperature to ideal gas. The thermal electron component describes the transition of free electrons from ideal degenerate gas to nondegenerate state. A formula is suggested which enables one to calculate the degree of ionization at arbitrary densities and temperatures. Continuous functions are described which approximate ionization potentials and energies. The phase diagram, shock adiabats for continuous and porous matter, and isentropes are calculated. An analytical approximation of the Debye function is suggested. The results are illustrated by dependences on compression ratio in the range ρ/ρ 0 = 1 to 10 6 . Comparison is made with experimental data.

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The dynamics of deformation in cylindrical liners are studied experimentally and theoretically in -pinch geometry, where the cylinders are deformed by a magnetic field created by a current flowing along the axis. This method allows one to obtain one-dimensional deformation and a reliable recording of magnetic field and cylinder deformation. The experiments are performed with a current amplitude of 0.8 - 3 MA and a current rise time of 2.5 - . Aluminium and copper tubes, from 4 to 6 mm in diameter and 0.25 - 1 mm wall thick, are compressed. The deformation rates under study are in the range of . The time dependence of the radii of the copper and aluminium tubes are measured with a streak camera and by the pulsed x-ray technique. The time resolution of the streak and x-ray photographs is 10 - 15 ns, their spatial resolution is . A rheological model describing the dynamics of compression is developed. The model includes the description of the metal as a plastic medium with moving dislocations in the solid state, and as a viscous medium in the liquid state. The one-dimensional solution to magneto-hydrodynamical equations of the liner dynamics is compared with the experimental results and thus the following rheological parameters of the metal are obtained: , the probability of dislocation generation in plastic deformation; and , the drag stress, the parameter which characterizes a drag force acting on the dislocation.