M. V. Khabibullin

Spall destruction of coarse-grained and ultrafine-grained titanium on exposure to nanosecond heavy-current electron beam

This paper presents results of experimental and theoretical research of spall destruction of volume coarse-grained and ultrafine-grained titanium when using it as a generator of shock wave of nanosecond relativistic heavy-current electron beam. Computer modeling of effect of an intensive electron beam on the condensed target has been carried out taking into account destruction, phase transitions, dependence of strength characteristics of materials on internal energy. This is considered within elastic, ideally plastic Prandtl-Reiss model. The results of calculations are compared with experimental data.

Development and Investigation of a Two-Layer Metal—Ceramic Material for Protective Barriers in Conditions of High-Speed Impact

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.

Prediction of the consequences of a high-velocity collision between meteoric particles and elements of a titanium alloy protective structure

Calculation-experimental studies of a high-velocity collision between VT1-0 titanium plates and ultrafine- and coarse-grained structures with a steel spherical impactor are illustrated. Fine-grained VT1-0 titanium plate samples have been obtained using the abc pressing method. Ballistic measurements have been performed using a 30-mm smooth-bore ballistic installation at velocities of about 2500 m/s. A high-velocity collision has been calculated in the scope of an elastoplastic model of interacting materials with regard to destruction and a different phase state at velocities reaching 15 km/s. It has been indicated that the mechanical properties of the VT1-0 alloy are improved when proceeding from a coarse-grained structure to an ultrafine- grained structure; however, in this case, the result of shock loading is hardly affected in the considered velocity range. Titanium plates can be used as screens to protect the main structure of the aircraft from a high-velocity collision.

High-speed impact of the metal projectile on the barrier containing porous corundum-based ceramics with chemically active filler

The paper presents a calculation-experimental study on high-speed interaction of the metal projectile with a combined barrier made of porous corundum-based ceramics filled with chemically active composition (sulfur, nitrate of potash) in the wide range of speeds. A mathematical behavior model of porous corundum-based ceramics with chemically active filler is developed within the scope of mechanics of continuous media taking into account the energy embedding from a possible chemical reaction between a projectile metal and filler at high-speed impact. Essential embedding of inlet heat is not observed in the considered range of impact speeds (2.5 … 8 km/s).

Special features of high-speed interaction of supercavitating solids in water

Special features of material behavior of a supercavitating projectile are investigated at various initial velocities of entering water on the basis of the developed stress-strain state model with possibility of destruction of solids when moving in water and interacting with various underwater barriers with the use of consistent methodological approach of mechanics of continuous media. The calculation-experimental method was used to study the modes of motion of supercavitating projectiles at sub- and supersonic velocities in water medium after acceleration in the barrelled accelerator, as well as their interaction with barriers. Issues of stabilization of the supercavitating projectile on the initial flight path in water were studied. Microphotographs of state of solids made of various materials, before and after interaction with water, at subsonic and supersonic velocities were presented. Supersonic velocity of the supercavitating projectile motion in water of 1590 m/s was recorded.