Hydrodynamic instabilities in solid media - from the object of investigation to the investigation tool

In the given review, we consider several types of experiments to demonstrate the application of the “perturbation method”, which is used to study the shock-wave melting of metals, to derive wide-range constitutive equations of the material and investigate the mesomechanics of deformation and fracture. Our investigation shows that shock waves induce thermal softening of metals up to the achievement of shock-wave melting parameters. The latter have been determined for some metals. Short-term “momentary” athermal softening of metals takes place behind the shock wave front owing to the formation of adiabatic shear planes. The inhomogeneity of metal deformation at the mesolevel is revealed. The dynamic hardening of metals and its quantitative indicators are found under quasi-isentropic loading of metals as compared to shock-wave loading. Wide-range constitutive equations of metals are derived. The fracture mechanisms of metals are found to change at volumetric expansion. The generalized dependences of shear instability development, its manifestation in the regimes not considered before and the ways of instability suppression are studied.