The high-velocity impact of a tungsten particle flux with the surface layer of steel (U8) samples is studied. High-speed photography which was used to record the motion of tungsten particles and detonation products shows that tungsten particles move with an average velocity of 2.4 km/s. Microstructure studies have revealed that upon the impact of tungsten particles with the surface of the target, the temperature in the active zone exceeds the temperature of the peritectoid reaction in the Fe-W system, and the polymorphic transformation of iron takes place with the formation of austenite and the dissolution of tungsten carbide in austenite under these temperature conditions.

Bronze alloys, due to their resistance to mechanical abrasion and high corrosion resistance, are used for the manufacture of machine parts and mechanisms that are subject to friction during operation. We present the results of studying the effect of shock-wave loading on the structure and properties of bronze alloys of grades BrAZh9-4 and BrAMts9-2. Shock-wave loading experiments were carried out by throwing the flyer plate onto cylindrical samples and compressing by a sliding detonation wave. The method of throwing a flyer plate accelerated by the energy of an explosion is often used to determine the spall strength of materials and the method of compression by a sliding detonation wave is used to create a large dynamic pressure inside the material. It is shown that at a throwing speed of a flyer plate of 2.4 km/sec, the impact pressure of the plate with the sample is 15 – 16 GPa, which exceeds the bronze shear strength. Under indicated loading conditions, the hardness of bronze increases by 53 and 25% for BrAZh9-4 and BrAMts9-2, respectively. Studies of the microstructure using scanning electron and optical microscopy revealed multiple cracks and micropores present on the surface of transverse sections forming a zone of spall fracture and areas turning into bands of localized deformation. Moreover, it is shown that when the samples are loaded with a flyer plate in a clip and without it, a greater number of cracks and shear areas are observed. Compression by a sliding detonation wave with a different amount of explosive charge revealed small defects present in the structure at the grain boundaries. The results obtained can be used to developed technologies for modifying and restoring the properties of bronze parts subject to shock-wave destruction.

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Shock-wave high-velocity impact of tungsten powder with a steel target was studied in the work. It is determined that shock wave treatment of the samples leads to a refinement, flattening and stretching of ferrite and perlite grains in the surface layer. The structural transition from plate perlite in the near-surface layer of the target to coarse-plate perlite in the bulk of the target, the microstructure of which does not differ from the microstructure of the initial sample, was detected in the structure of U8 steel after a particle flux. It is found that cellular supercooled austenite with tungsten carbide mesh along grain boundaries is formed in the structure of steel. The microhardness of the target in depth after exposure to tungsten particles is analyzed. It was shown that the microhardness distribution along the width of the sample is wave-like, and the microhardness decreases monotonically along the depth of the sample. The microhardness maximizes by 24% at a distance of 4 mm from the surface compared to the original microhardness.