Hydrodynamic instabilities and dynamic strength

The paper presents results of numerical-theoretical and experimental investigations of influence of shear strength on growth of the Richtmyer-Meshkov instability and the Rayleigh-Taylor instability. It is revealed that, for monochromatic perturbations at accelerated boundary of a solid, there are the critical conditions when the perturbation growth is limited. High sensitivity of perturbation growth to dynamic strength near the stability boundary allowed to develop the method for determination of dynamic strengths of substances in wide range of pressures and strain rates (? $\sim$ 10 $\div$ 300 GPa, strain rate $\sim$ 10E4 $\div$ 10E7 1/s). The paper includes setup and results of series of tests devoted to investigation of dynamic strengths of some metals (??, ?u, AL, Be).