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The paper presents the results of numerical modeling of dynamic loading of a target made of 2024 aluminum alloy with a steel projectile of cylindrical shape. A comparative analysis of the application of two different fracture criteria to the numerical simulation of the deformations process of the targets material was conducted. In one case, the process of destruction of the material of the target was simulated using the fracture criterion based on accumulated plastic deformations. In the other case the Hoffman fracture criterion recorded through full stresses was used. The obtained calculation results were compared with experimental data for a loading velocity of 151 m/s. [ABSTRACT FROM AUTHOR]

The paper presents the results of numerical simulation of the dynamic loading of a target from an anisotropic aluminum alloy AA7010-T6 with an isotropic aluminum projectile with different velocities. The process of destruction of an anisotropic target material was simulated by applying the fracture criterion from accumulated plastic deformations. This criterion makes it possible to take into account the anisotropy of the strength characteristics of the target material and to simulate the process of accumulation of microdamages. To study the effect of anisotropy of the mechanical characteristics of the material on its deformation, two types of calculations were carried out: in the first case, the mechanical properties of the target material along the loading direction were minimal, and in the second case, maximal. This statement of the problem corresponds to the statement of the problem in natural experiments in which the direction of the material rolling is oriented parallel or perpendicular to the direction of the load. [ABSTRACT FROM AUTHOR]

The paper presents the results of numerical simulation of the dynamic loading of an target from an anisotropic aluminum alloy 2024 by an isotropic aluminum projectile. The process of spalling destruction of an anisotropic target material was modeled with the help of two models of elastoplastic deformation of the material, in the first case the fracture criterion from accumulated plastic strains. In the second case, the elastoplastic material deformation model is supplemented by a fracture criterion containing the ultimate porosity. The obtained results of the calculations were compared with the experimental data for the case of the initial shock loading rate of 630 m/s. Numerical modeling of spall destruction of target is performed by the finite element method in a three-dimensional formulation. [ABSTRACT FROM AUTHOR]

Numerical modeling of spalling brittle fracture along the (0001) plane in a zinc single crystal under shock loading by an aluminum projectile was performed in the work. Numerical modeling was carried out by the finite element method in a three-dimensional statement. The mathematical model allows to take into account the anisotropy of bulk compressibility in a single crystal of zinc, auxeticity, anisotropy of the propagation velocities of elastic longitudinal and volume waves. Stresses are determined on the basis of a comparison of velocity profiles of the rear surfaces of targets from zinc single crystal in mutually perpendicular directions when it is destroyed along the (0001) plane in natural experiments and numerical simulation. [ABSTRACT FROM AUTHOR]

Numerical simulation of spall destruction of an aluminum single crystal in a three-dimensional statement is carried out in this work. The velocity profiles of the rear surfaces of targets from aluminum single crystals are obtained. A comparison of these velocity profiles with those obtained by other authors as well as with the results of natural experiments is made. Shock loading of an aluminum single crystal is carried out taking into account the anisotropy of its mechanical properties. Spalling is modeled within the framework of continuum mechanics. [ABSTRACT FROM AUTHOR]

The study represents the analysis of numerical simulation of the failure of aluminum targets made of highly porous or solid 2024 alloy under dynamic loading. The calculations employed the finite elements method in threedimensional formulation with the use of proprietary programs. The article presents the results of the numerical simulation of Taylor's test for the projectile made of highly porous aluminum 2024 alloy at the velocities of 75 to 175 m/s. These results are in a good agreement with the results of the experiments. The peculiarities of the destruction of highly porous aluminum targets are shown. [ABSTRACT FROM AUTHOR]

The failure criteria of anisotropic materials, the criteria being expressed via deformations, are rarely applied in practice, and are usually used for low-ductility materials. Another situation involves the simulation of failures in materials with the high anisotropy of mechanical properties and that suffer elastic-brittle fracture. For such materials the failure criteria are formulated using ultimate strains and strain tensor invariants. For simulating the fractures of materials that are characterized by the anisotropy of strength properties, the failure criteria are applied with the critical values of stresses and strains, as well as their intensities. Using the value of cumulative plastic strain as a failure criterion does reflect the anisotropy of elastic and plastic properties of a material, but it does not reflect that of the strength properties. The application of this method allows accounting the total plastic strain induced by tension and compression in the conditions of the wave strain of targets during their impact loading. [ABSTRACT FROM AUTHOR]