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Using high-resolution scanning and transmission electron microscopy methods, the morphological and size characteristics of the structural components of the composites synthesized on the basis of aluminum with a graphene microadditive in a commercial aluminum melt under a layer of molten salt are studied. An experiment on the dynamic compression of a composite by the Kolsky method was performed, the evolution of a cast structure during high-rate deformation is studied, and mechanical characteristics in the range of deformation rates έ = 1.8–4.7 × 103 s–1 were measured. The dynamic characteristics of the composite were measured under conditions of loading with planar shock waves (έ = 5 × 105 s–1) for the first time. The dynamic properties of the composite are compared as functions of the graphene content in the aluminum matrix.

New experimental data on the dynamic strength of the lead-antimony (2.77%) alloy comprised of different structures formed after thermal treatment in various regimes are presented in this work. The optimal alloy thermal treatment regime (quenching from 250°C) providing the best strength characteristics under explosion or high-speed impact is revealed.

—The dynamic properties of commercial copper (99.8 wt % purity) with a submicrocrystalline and nanocrystalline structure obtained by high-strain-rate deformation using the dynamic channel-angular pressing (DCAP) method have been studied in this work. The tests were carried out under conditions of shock compression at a pressure of 5.6−6.8 GPa at a strain-rate of (0.9−2.0) × 105 s–1. The analysis of the evolution of the structure and mechanical properties, namely, the dynamic elastic limit, dynamic yield stress, and the spall strength of copper before and after DCAP in different regimes, made it possible to evaluate the influence of the dispersity and imperfection of the crystal structure on its resistance to the high-strain-rate deformation and fracture. It has been shown that the grain refinement from 100 to 0.5−1.0 μm increased the dynamic elastic limit and the dynamic yield stress of copper by six times, but only slightly decreased the spall strength. The further refinement of the structure (up to 0.05−0.40 μm) increases the spall strength of copper by 1.4 times as compared to its value in the initial coarse-grained state.