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Universal features of dynamic failure and turbulence phenomena are considered on the basis of results of research and analyses of published data. The absorbed energy density causing the failure is comparable to the energy parameter of the crystal lattice E, which is fractions of electronvolt per atom in the range of nonequilibrium states t ~ 3 × 10–6–10–10 s. Macrofailure, changing the body connectivity, arises when approaching the critical density of the failure center cascade, i.e., percolation cluster, through the cascade of bifurcations. Fully developed turbulence is a chaotic dynamics, which is related to the stochastic instability of the transition through a sequence of period-doubling bifurcations, through intermittency, etc. At present, a strict mathematically grounded theory of dynamic failure phenomena of condensed matters and turbulence theories are absent, which implies the application of scaling relations and phenomenological approaches for their description. On the basis of design-theoretical studies and analysis of published data, it has been shown that phenomena of dynamic metal failure and fully developed turbulence are analogous, meaning that these processes have close values of critical exponents and belong to one universality class. [ABSTRACT FROM AUTHOR]

The phenomenon of dynamic chaos and self-organization is related to stochastic instability and critical behavior of nonlinear physical systems of various nature. These processes occur, e.g., in the dynamic failure phenomenon of condensed media and fully developed turbulence. In such nonlinear systems, a cascade of dynamic dissipative structure with a fractal structure arises. Multifractal properties are characterized by the spectral function f(dfi), determined by the behavior of the number of elements l required to cover the fractal sets with the similar probabilities Pi~ . In both cases, the transit of systems from one scale-time level to the next one via a cascade of bifurcation and quantitative process characteristics at developed stages do not depend on the Hamiltonian of interatomic interaction. The fractal organization of processes at all scale-time levels testifies to the process similarity and allows us to attribute these processes to a single class of universality. The evolution of the system as a whole is determined not by the interatomic interaction Hamiltonians, but by the incipient cascades of dissipative structures. The close values of fractal dimensions on all the studied scales, which characterize the failure structure, allow us to study the formation of micro-flaws of failure and macro-failure as the scale edges of the spectrum of a single process that has common order parameters. [ABSTRACT FROM AUTHOR]

The general regularities of dynamic destructive processes (dynamic fracturing and dispersion) in metals on high-intensity exposure in the dynamic range of nonequilibrium states of t ~ 10–6–10–9 s have been found. The equation of compressibility (susceptibility) of the loaded sample that depends on the density of fracture centers is derived using the pair potential of the crystal lattice. The general regularities for nonequilibrium systems make it possible to predict the behavior of unstudied systems. The behavior of plutonium metal, thorium, and uranium in the range of nonequilibrium states of t ~ 10–6–10–9 s and E ~ 30–300 J g–1 is predicted using the time invariant of the behavior of metals under extreme conditions and experimental data on the critical pressure leading to the destruction of plutonium metal. [ABSTRACT FROM AUTHOR]