One commonly used method for characterizing the dynamic characteristics of materials is the Taylor impact test. This method measures the dynamic yield strength of cylindrical specimens and determines material model constants required for the numerical simulation of the behavior of materials subjected to high-velocity deformation. The purpose of this work is to investigate the microhardness and microstructure of copper specimens at different impact velocities using the Taylor impact test. This paper describes experiments performed on copper specimens (OFHC 99.9%, M1) using a single-stage light-gas gun with impact velocities in the range of 150–450 m/s. After impact, the specimens were cut along the symmetry axis to measure the microhardness and the grain size of the microstructure. Microhardness in the entire area exceeded the initial value for all investigated velocities. The averaged microhardness curves were obtained for each specimen to identify four deformation zones and determine their dimensions depending on the impact velocity. The average grain size in the entire deformed specimen became smaller than in the starting specimen. The study of the microstructure of the specimens has shown that the grain size distribution corresponds to the four deformation zones in the copper specimens.

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Abstract.A new approach to manufacture of metallic-intermetallic laminate (MIL) composites is realized: explosive welding of a package of titanium and aluminum sheets with the subsequent sintering without a hydraulic press. Sheets of the titanium (thicknesses of 0.5 and 0.6 mm), aluminum (thickness of 1.0 mm) were used. Packages with 11, 13 and 21 alternating Ti-Al layers in the sizes 50х120 and 120х300 mm were used. The processes of high-velocity interaction of a projectile with the MIL composite target were numerically investigated in axisymmetric geometry using modified finite element method. Results of computations demonstrate that the optimal composite target has higher ballistic resistance in comparison with a uniform target made of either Al 3 Ti or Ti-6-4.