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The ballistic resistance of a combined cermet material based on a high-hardness ceramic bound with an intermetallide on a high-strength metal substrate, (TiB2 + NiTi) + Ti, is compared with that of plates of steel, VT1-0 titanium alloy, and Al2O3 corundum ceramics upon an impact with a steel spherical impactor in the region of velocities of about 2500 m/s. Experimental studies of protective barriers upon a high-speed impact were conducted using an experimental high-speed ballistic test bench. Mathematical modeling is based on a model of porous elastoplastic medium with allowance for various mechanisms of material destruction, which was modified for media with a complex composition. It is shown that, in the considered range of impact velocities, during penetration of barriers, the (TiB2 + NiTi) + Ti material, despite its low surface density, exerts a greater force on the impactor and exhibits greater penetration resistance than steel, titanium, and ceramics. [ABSTRACT FROM AUTHOR]

We propose a series of experiments aimed at analysis of peculiarities and revealing general regularities in the penetrability of strikers made of a composite material based on tungsten + nickel + iron + cobalt alloy with an admixture of highly rigid refractory titanium–tungsten carbide particles in various initial conditions. In particular, we have analyzed the effect of the initial temperature of the striker in the interval from –50 to 50°C on the penetration into a steel obstacle experimentally and by calculations. It is found that the initial temperature of the striker does not noticeably affect the penetration depth in the obstacle at impact velocities up to 2500 m/s. The penetrability is found to be 20% higher than that for a monolithic massive analog made of VNZh-90 alloy. [ABSTRACT FROM AUTHOR]

In this study, we perform calculations and experimental studies of the destruction of composite impactors from a porous tungsten–nickel–iron–cobalt alloy with 10 wt % tungsten titanium carbide at high-speed impact with steel barriers. In ballistic tests over a wide range of velocities, there is a significant excess of the penetration depth of these impactors into steel barriers compared to the mass-dimensional analog of a tungsten–nickel–iron alloy with 90% tungsten content. Based on the analysis of crater morphology and the structure of impactor fragments after introduction into the obstacle, we assume that the impactor is "self-sharpened" by localizing plastic deformation, which reduces the effective interaction area and increases the penetration depth. To describe the destruction, we modified the mathematical model of a porous ideal elastic-plastic body with a complex structure with the possibility of considering the adiabatic shear mechanism during interaction between the impactor and the obstacle. [ABSTRACT FROM AUTHOR]

The possibility of improving the physico-mechanical characteristics of composite materials used in protective structures against a high-speed impact is considered. By means of self-propagating high-temperature synthesis, a two-layer cermet is obtained: the front layer is a cermet based on titanium diboride with a titanium nickelide bond, and the back layer is a titanium alloy. The study by the computational-experimental method of the impact resistance of this composite in comparison with a homogeneous titanium plate showed a qualitative advantage expressed in the absence of a shock crater in a cermet plate after a collision with a steel spherical impactor and stronger deformation and prefracture of the impactor. The two-layer cermet has a high resistance to the penetration of the steel impactor. [ABSTRACT FROM AUTHOR]

An attempt is made to create an electric-discharge source for pumping argon, krypton, and xenon dimer lasers. The device is based on a method proposed previously by the authors, wherein confinement of the discharge is achieved by removing the cathode spot from the main discharge region and closing the discharge to the spot along a narrow extended auxiliary plasma channel. The conditions for the formation of such a discharge are investigated. The high stability of the sparkless stage of the discharge permits the first-ever attainment of energy depositions at the level of 100 J/cm² at pressures ∼ 10 atm, a level several orders of magnitude higher than is attainable by conventional methods. A discharge cell and power supply system are designed for a multisectional discharge with an active length of 200 mm, and the reliability of the entire apparatus is demonstrated in long-term use. [ABSTRACT FROM AUTHOR]

Water degassing and removal of salts by high-power acoustic pulses are analyzed. A model explaining the mechanisms of these processes is proposed. [ABSTRACT FROM AUTHOR]