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The patterns of plastic flow localization in high-manganese γ-Fe FCC single crystals undergoing the twinning while stretched are obtained by the experimental procedure of double-exposure laser speckle photography, which permits accurate in situ measurement of plastic distortion tensor components during specimen loading and analysis of local strain distributions over the tested specimen. Basic spatiotemporal features of strain localization at the stages of yield plateau, easy glide, and linear hardening are established. The type of ordered space-time arrangement of localization nuclei, i.e. the type of localized deformation wave, which is observed for the respective flow stage (yield plateau, easy glide, linear and parabolic work hardening), is determined by the acting law of work hardening. The velocity of strain localization sites moving upon stretching is determined. Conditions under which plasticity autowaves appear in the strained medium are discussed. It is demonstrated that the local strain distributions in the case of twinning are similar to those due to dislocation glide.

We perform the numerical simulation of slow deformation autowave perturbations of inelastic nature in an elastic-plastic medium. We show that these perturbations exhibit the properties of solitons during interactions. They penetrate each other or repel from one another as elastic particles. The properties of these deformation solitons are similar to the solitons obtained from the solutions of the Korteweg-de Vries and sine-Gordon equations. We demonstrate that slow deformation fronts actively participate in the formation of the fracture foci, being an effective mechanism for the transfer and redistribution of energy in a loaded medium.

The deformation of materials with unstable phase structure such as titanium nickelide (nitinol) and steel with transformation induced plasticity (trip-steel) was studied within the framework of the autowave theory. It was established that at the initial stages of deformation a strain induced martensitic phase transformation occurs in both materials, which is realized as switching autowaves of localized plastic deformation. In nitinol it occurs completely, while in TRIP steel the remaining unstable austenite under further deformation expose a transformation similar to the Portevin–Le Chatelier effect with formation of waves of excitation of localized plastic deformation.

A new approach to the problem of the plastic flow of solid crystals is proposed. This approach is based on studying the macroscopic localization patterns of plastic deformation, which can be considered as different types of autowave processes of defect self-organization. An unambiguous correspondence between the localization patterns and stages of plastic flow in metals is established. A new model is proposed to describe the development of plastic flow localization. A change-over in the patterns of autowave processes of plastic flow evolution and a transition to fracture are attributed to the specific features of the interaction between information and dynamic subsystems.

The research was performed for polycrystalline aluminum by steady-state creep. It is known that at the macro-scale level, deformation exhibits localized behavior. The localization patterns would propagate over the deforming sample by steady-state creep, forming thereby a kind of phase autowave. The rate of phase autowave increases with the growing extent of straining. It is demonstrated that the processes controlling the autowave rate have the same activation volume as the processes controlling the creep rate.

The paper presents the proprietary know-how of the autowave analysis which occur at deformation of solids. Traditional techniques of X-ray diffraction analysis are described to detect main autowave properties, i.e. wave propagation velocity and length.

The parameters of localization patterns emerging at the linear stage of work hardening are discussed in the frame of autowave concept. The stress-strain diagrams have been plotted for the test samples of metals exposed to active loading. It is found that the product of phase autowave velocity and length has the same order of magnitude as the product of elastic wave rate and the lattice constant of the respective metal; hence, this quantity can be regarded aselastic-plastic invariant. The invariant is found to vary in a regular manner with the shear modulus, modulus of dilatation and interplanar spacing. The data obtained for elements of one and the same period of Mendeleev's table of elements are found to vary monotonically; however, after changing over to the next period, a jump-wise variation in the data would occur. It can thus be concluded that the elastic-plastic invariant is a dominant characteristic of plasticity;the nature of the invariant is related to the lattice properties and the phonon density of crystal lattice.

The generation of leading centers was observed in an oscillatory reaction of the Belousov‐Zhabotinsky type under the action of collimated radiation with high linear energy transfer. Threshold values of the absorbed dose for the generation and complete quenching of autowaves were estimated. For modeling the effect of hard ionizing radiation on the Belousov‐Zhabotinsky reaction, we proposed a modified radicalator model taking into account the interaction of reactants with ⋅OH radical, which is produced in the course of irradiation as a result of the radiolysis of water.

It is investigated the solutions of a general acoustical equation, describing in the second order perturbation theory a nonlinear evolution of wide spectrum acoustical disturbances in nonequilibrium media with one relaxation process. Its low‐ and high‐ frequency limits correspond to Kuramoto‐Sivashinsky equation and the Burgers equation with a source, respectively. Stationary structures of general equation, the conditions of their establishment and all their parameters are found analytically and numerically. It is obtained the condition of instability of a disturbance that has a step‐like initial form. In acoustically active media it is predicted the existence of the stationary periodical roll waves and the solitary pulse with the shock front and the exponential tail. These periodical waves and solitary pulse are autowaves. Their parameters depend only on nonequilibrium medium properties.