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The behavior of characteristics of localized plastic flow autowaves in a Fe–Cr–Ni alloy in the temperature interval of 143 ≤ T ≤ 420 K (0.34 ≤ T/ΘD ≤ 1), where ΘD = 420 K is the Debye temperature (parameter), is considered. It is shown that the product of the length and propagation rate of the autowave λVaw in this interval decreases with temperature. At the same time, the ratio of this quantity to viscosity of the photon gas in the metal in the investigated temperature interval remains almost constant. This indicates that the elastoplastic strain invariant does not depend on temperature.

An analytical method for determining the amplitude and velocity of an autowave pulse emerging in isentropically unstable heat-releasing media is presented. The method is suitable for any values of acoustic dispersion and growth rate and requires the knowledge of heat-loss function only without the need for a numerical solution of a complete system of gas-dynamic equations.

The relationship between the spatial parameter of the development of a localized plastic flow (the length of the localized plasticity autowave) and the length of the deformed sample is studied. According to experiments carried out on polycrystalline samples of a zirconium alloy and commercial purity aluminum, these quantities are related to each other by a logarithmic law valid at the stage of parabolic strain hardening.

The evolution of gas-dynamic perturbations in a heat-releasing medium was investigated in two-dimensional geometry under conditions of isentropic instability. Decomposition of the initial perturbation of “step” type, possessing transversal modulation (ripples) of front, into a sequence of flat autowave fronts predicted by a generalized nonlinear acoustic equation is shown. Evolution of localized perturbation results in decomposition into sequence of concentric autowaves. The front of two-dimensional structures is resistant to transversal modulation. A quasi-regular cellular structure is formed behind the fronts.

Results of measurements of the coefficient of microwave reflection from a block of freshwater ice subjected to plastic deformation are presented. Strong fluctuations in the phase of reflection coefficient are revealed, with the extremum at an electromagnetic radiation wavelength of 1.35 cm. This wavelength corresponds to the region of localized plastic flow autowaves in crystalline media.

The correlation between lattice characteristics of a deformed medium and parameters of autowaves of a localized plastic flow in metals at the stage of linear strain hardening is considered. Such correlation testifies for the existence of a close connection between elastic and plastic deformations of the medium and, more generally, between characteristics of plasticity and electronic structure of elements.

A correlation between the characteristics of localized plasticity autowaves and the Debye temperature of crystalline lattice in 19 metals has been analyzed. It is shown that this experimentally established linear dependence follows from the previously introduced elastoplastic invariant of deformation that relates the parameters of elastic and plastic processes in a deformable medium.

An equation describing the evolution of fast and slow magnetoacoustic waves in a heat-releasing completely ionized gas has been obtained. The shape and parameters of the magnetoacoustic pulse that is an automodel solution of this equation under conditions of magnetoacoustic instability have been determined.

Plastic strain localization patterns in compression-strained alkali halide (NaCl, KCl, and LiF) crystals have been studied using a double-exposure speckle photography technique. The main parameters of strain localization autowaves at the linear stages of deformation hardening in alkali halide crystals have been determined. A quantitative relationship between the macroscopic parameters of plastic flow localization and microscopic parameters of strained alkali halide crystals has been established.

Characteristics of the plastic strain macrolocalization are compared to parameters of the Hall-Petch relation for the flow stress in polycrystalline aluminum samples with grain sizes ranging from 0.008 to 5 mm. It is established that, in the range of brain sizes studied, there are two possible types of the dependence of the length of localized strain autowave on the grain size and two variants of the Hall-Petch relation. It is shown that the boundary between the two variants in both cases corresponds to d ≈ 0.1 mm. Interconnection of the patterns of plastic flow localization and the Hall-Petch relation is traced.

An analysis is made of the evolution of local deformations during the elongation of samples of fine-grained zirconium alloy. It is established that the deformation distribution patterns exhibit ordered behavior where the types of ordering are closely related to the stages of the deformation curve. The results are compared with similar data from studies of the deformation fields of single-crystal and polycrystalline materials with different types of crystal structures and deformation micromechanisms. It is noted that all these similar results, including those of the present study, may be interpreted using autowave representations.

Using the well-known property of the focusing of hollow beams, it is shown that a highabsorption domain can be created in the end of a sample cell. The results can serve as one method of recording information in the interior of a medium. The implementation of such a domain can serve as a new mechanism for developing autowave processes for varying the output intensity of a light beam.

Autowave dynamics in a two-dimensional lattice of excitable elements of the FitzHugh-Nagumo type containing topological defects has been studied. It is shown that the core of a spiral wave can drift along a path composed of such defects. The possibility of controlling the motion of spiral waves in excitable and oscillating media is considered.