We present the results of experimental investigations of the temperature behaviors of the volt-ampere characteristics of Tl4HgI6 and Tl4CdI6 crystals. The temperature dependence of resistance is analyzed and the resistivities of the samples at room temperature are determined. The activation energy is computed and the dynamics of changes in the temperature coefficient of resistance is determined for

The problem of free vibrations of a cylindrical shell is solved by using numerical and analytic methods. The maximum error of numerical calculations as compared with the analytic solution is established.

On the basis of the proposed model, we study the phase and stressed states of titanium-nickelide plates under the conditions of bending and heating-and-cooling by using the methods of continuum mechanics and thermodynamics of nonequilibrium processes with an aim to get a quantitative description of the behavior of bodies made of shape memory materials. We perform calculations for various combinations

We proposed a new theory of bending of axisymmetrically loaded plates in the form of thick rings or disks for the case where their deflections are not large and the stressed state is not described by the Kirchhoff–Love or Timoshenko hypotheses. For bending of this kind, we use two harmonic functions that describe the axisymmetric stressed state. After integration over the thickness of the plate, the

We compare the dislocation model with a new discrete model of plasticity. According to the previously proposed model, a crystal lattice with spherically symmetric potential of interatomic interaction is unstable under shear stresses in the internal regions of the crystal. The surface layers preserve the unstable crystal lattice, which creates the state of unstable equilibrium in the crystal. As an

We study the wear resistance of the disks of furrow-openers of seeding machines made of 65G steel under the conditions of dry abrasive friction. It is shown that the procedure of quenching with lowtemperature tempering makes the wear resistances of samples of 65G steel 2.6 and 13 times higher in the cases of testing with nonfixed and fixed abrasives, respectively. This means that heat treatment increases

We present the results of comparative investigations of the quality of Me–Cr–Al–Y tube cathodes obtained by the methods of casting and granule metallurgy. The quality of coatings applied to turbine blades by the method of ion-plasma deposition is evaluated by the method of X-ray diffraction microanalysis. The influence of the technology of production of cathodes on the surface roughness of the coatings

To create blades of gas-turbine engines of new generation made of materials based on alloys of the Nb–Si system, we study the surface layer formed on niobium by its silicides with additionally introduced titanium elements. It is shown that the heat resistance of these specimens does not depend on the method of formation of the surface layer and depends only on its thickness. The addition of titanium

We study the problem of tension of a spherical shell reinforced by a flexible coating and weakened by a meridional crack. The coating is modeled by a hinge connecting the faces of the cut on one of the face surfaces of the shell. The stressed state near the crack tips and the distribution of the hinge reaction over the coating are determined by the method of singular integral equations. The limit state

We study the influence of the voltage (100–180 V) of plasma-electrolytic oxidation on the formation of hydroxyapatite coatings on VT1-0 commercially pure titanium in alkaline electrolytes (hydroxyapatite + 1 M potassium hydroxide). We analyze the physical and chemical characteristics of hydroxyapatite coatings (phase composition, thickness, porosity, and surface roughness) and establish the conditions

According to the results of X-ray and complex thermogravimetric analyses, we establish the influence of nucleation agents based on polyvinylpyrrolidone and sodium liquid glass on the morphology of polypropylene. It is shown that the introduction of nucleation agents increases the degree of crystallinity of polypropylene and promotes a decrease in the sizes of crystallites. In this case, the most pronounced

We study the Ga–In–Sn eutectic-catalyzed interaction of aluminum alloys with water resulting in the process of hydrolysis and generation of hydrogen. The aluminum alloys were prepared by melting aluminum with additions of Ga–In–Sn eutectic (5 wt.%), bismuth (3 wt.%), or antimony (3 wt.%). The temperature-dependent kinetics of their hydrolysis in a temperature range 25–70°C is studied by using a volumetric

We study new biomedical alloys of the Ti–18Nb– x Si system with 0.6–1.2 wt.% Si both in the as-cast state and quenched in water after holding at temperatures from 800 to 1200°С. It is shown that their solid-solution hardening within certain temperature ranges is supplemented by dispersion hardening with silicides. Rapid cooling after melting promotes the formation of nonequilibrium partially quenched

We study welded joints of sheets 4 mm in thickness made of D16T alloy (an analog of 2024-Т3 alloy) in the as-delivered state (hardening and natural aging) and after additional artificial aging. The joints are obtained by fusion welding with the use of the pulsed-arc method with consumable electrode (Zv1201). It is shown that, for some modes of heat-treatment of the welded alloy and welded joint, the

The results of fatigue tests of samples made of S355JR steel under random tension-compression with nonzero mean stress are presented. The procedure of experimental research is described. The obtained experimental results are presented with the use of Wöhler fatigue graphs. The algorithm for the determination of the fatigue life uses, among other things, a rainflow cycle counting procedure, as well

We study the corrosion resistance of high-entropy alloys of the Cr–Fe–Mn–Ni system in lead melts at 480°С in testing for up to 1000 h. It is shown that the compatibility of these alloys with melts is determined by the processes of dissolution of chromium, nickel, and manganese in lead and the diffusion of oxygen from the melt. It is demonstrated that the dispersion hardening with radiation-resistant

We study the corrosion of carbon steel in chloride-containing corrosive media inhibited by xanthan gum and its composition with a biogenic surfactant. It is shown that the xanthan biopolymer is an efficient corrosion inhibitor in steel due to the adsorption and formation of complexes with iron ions. The addition of trehalose lipid surfactants to corrosive media synergistically enhances the action of

The thickness of plastically deformed layer formed under the conditions of quasibrittle fracture as a result of propagation of a preliminarily formed fatigue crack is found as a result of X-ray investigations. We estimate the residual stresses of the second kind. By using these stresses, we compute the specific fracture energy. It is shown that the thickness of plastically deformed layer coincides

We study welded joints (WJ) of plates 6–8 mm in thickness obtained by the electric-arc and laser methods with various values of the energy of welding Ω. The strains and stresses in the stretched plates with welds are computed numerically by using the ABAQUS program. The characteristics of materials in the modeled WJ are obtained according to the results of testing minispecimens cut out from the appropriate

We study the influence of modification of the surface layer of a metal in gaseous atmospheres on the long-term strength of Zr–1% Nb alloy at room temperature (20°С). It is discovered that the procedures of treatment in oxygen-containing (580°С; 1.33 Pa; 0.5 h under a pressure of 1.33∙10–2 Pa , and τ = 2.5 h) and nitrogen-containing (580°С; 1.33∙10– 3Pa; 1 h under a nitrogen pressure of 1∙105 Pa , and