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The roll bonding of an experimental Al-2%Cu-2%Mn alloy with technically pure 1050A aluminum at true deformations of 0.26, 0.33 and 0.40 has been simulated using the QForm 10.3.0 FEM software. The flow stress of the Al-2%Cu-2%Mn alloy has been measured in temperature and strain rate ranges of 350–450 °C and 0.1–20 s−1, respectively. The simulation results suggest that the equivalent strain in the cladding layer is more intense than that in the base layer, reaching 1.0, 1.4 and 2.0 at strains of 0.26, 0.33 and 0.40, respectively. The latter fact favors a decrease in the difference between the flow stresses of the rolled sheet layer contact surfaces by an average of 25% at the highest strain. The experimental roll bonding has achieved good layer adhesion for all the test samples. The average peeling strength of the samples produced at strains of 0.26 and 0.33 proves to be 12.6 and 18.4 N/mm, respectively, and at a strain of 0.40, it has exceeded the flow stress of the 1050A alloy cladding layer. The change in the rolling force for different rolling routes has demonstrated the best fit with the experimental data.

We propose a new approach for railway path diagnostics on the basis of track line stress–strain analysis using the data provided by high-precision accelerometers. This type of sensor provides sufficient accuracy with lower costs, and enables the development of a railway digital twin, according to the concept of the Internet of Things. The installation of sensors on a railway track along its entire length allows real-time monitoring of the states of the technical parameters of the railway track, and using mathematical methods to evaluate its wear on the basis of constantly received data. This paper presents an original 3D model of a railway track line and the results of its analysis using a finite element method. To test the model, we performed an analysis of the normal stresses and deformations in the elements of a railway track by simulating the impact of rolling stock on a section of a railway track with intermediate rail fastenings, ZhBR-65SH. The research results were probated and tested at the testing ground of the Kuibyshev branch of Russian Railways, the Samara track. The proposed approach makes it possible to determine the load of the track, and knowing the movement of the rail, to calculate the structural stress in the elements of the railway track, to constantly monitor the parameters of the slope and rail subsidence.

The paper reviews the theory of technical evaluation of the containment and the experience of using the mobile geodetic diagnostic system at the nuclear power plant unit No. 4 of Rostov NPS. The paper considers the results of a regular built-in system designed to determine and evaluate the strain-stress state of containments during the acceptance in service, commissioning stage and operating period. A comparison with the results of the geodetic system obtained at the same stages of containment existence.

The paper considers the problem of ensuring the reliability of experimental data obtained by tensometric studies of existing power plants. A technique that allows taking into account the change in the metrological characteristics of high-temperature strain gauges has been proposed. The design of the installation for determining the sensitivity of strain gages at temperatures up to 700°C has been considered.

In this work, p-type thermoelectric material was produced by hot extrusion of pre-synthesized in injection molding machine Bi0.5Sb1.5Te3 solid solution. During the research radial distribution of the Seebeck coefficient was confirmed and described in material’s cross section using thermal measuring probe. Such nonuniformity of the Seebeck coefficient is correlated with the strain-stress state of extrudate specifically with the distribution of accumulated strain intensity, which was obtained by mathematical modeling of extrusion process using the software package DEFORM.

The present article is focused on the rolling of powder tapes. A mathematical model of rolling a powder core in a metal cover is developed based on splitting a consolidation zone into a final set of elementary volumes. The main computational approach is based on the joint solution of the condition of static balance of the elementary volume and the condition of plasticity of porous materials in tension in a final and differential form. During experimental studies, the influence of cover thickness on the course of rolling powder materials is established. Thus, the more cover thickness, the higher its rigidity and elastic deflection. It reduces the extent of the deformation center, power parameters of the process, and deformation of the powder component. Also, the parameters of physical–mechanical properties of powder materials which enter into a condition of plasticity for porous materials were investigated.

The present study was aimed at determining the surface strain/stress state in an Ni-based single-crystal (SC) superalloy that was subjected to two different cooling rates from solid solution temperature through using the X-ray diffraction (XRD) method. The normal stresses σ 11 s and σ 22 s were determined, then the Von Mises stresses ( σ V M s ) were derived from them. Field emission gun scanning electron microscope (FEG-SEM) and transmission electron microscope (TEM) micrographs were taken to illustrate the strain/stress state change. The precipitation of the secondary γ′ phases in the γ phase and the formation of the dislocation in the interphase upon a slower cooling rate caused the γ phase lattice distortion to increase, so a larger σ V M s of the γ phase was realized in comparison to the faster cooling sample. For both of the two cooling modes, we found that the σ V M s of the γ′ phase increased due to the growth of the γ′ phase during the aging process. Also, the aging process led to pronouncedly anisotropic lattice mismatches in the 331 and 004 planes. In addition, the surface strain/stress states of a cylinder sample and a tetragonal sample were also studied using a faster cooling rate, and σ 11 s and σ 22 s were analyzed to explain the influence of the shape factor on the stress anisotropy in the [001] and [ 1 1 ¯ 0 ] orientations. The strain in the [001] orientation of the γ phase is more sensitive to the shape change.

Urban subsurface space is considered to be a dynamic multicomponent system, which includes sandy-clayey soils, groundwater in different state, microbiota, gases, and underground facilities (either as foundations or as surrounding walls), or engineering structures (tunnels of different purpose, hazardous industrial-waste storages, etc.). Special attention is paid to the significance of hydrogeological studies, primarily, to the influence of hydrodynamic and physicochemical conditions and aquifer chemistry on soils, stress and strain state of the stratum, deformation of structures, and the formation of corrosiveness of subsurface medium. The main factors that govern groundwater composition within zones with different contamination level in megacity territory are analyzed. Results of studying the effect of various aquifers on the conditions of construction and operation of above-ground and subsurface structures are presented. Recommendations for assessing the hydrogeological conditions as a part of geotechnical survey are given.

Rational reduction and tension schedules and roll profiles for 150/500×400 four-high reversing mill and 350×450 two-high reversing mill were developed and studied to increase the output of strips of high accuracy. For the 150/500×400 mill, increasing the work roll crown from +0.1 to +0.15 mm, the specific back tension from 0.12–0.16 to 0.14–0.18 МРа, and the specific front tension from 0.16–0.18 to 0.18–0.20 MPa appeared to decrease the transverse thickness deviation of strips by 10% compared with the conventional reduction and tension schedules. For the 350×450 mill, increasing the work roll crown from +(0.04–0.07) to +0.09 mm, the specific back tension from 3.3 to 8.7 MPa, and the specific front tension from 4.44 to 10.0 МРа appeared to decrease the transverse thickness deviation of 1-mm strips to 0.039 mm, which may be considered high accuracy. A mathematical model is proposed to analyze the stress-strain state of wavy strips with allowance for hardening. The numerical modeling showed that the tangential stresses are maximum on the upper and lower faces of a 0.5h1 strip, while the radial stresses are maximum in the neutral plane of the strip.

The influence of the azimuthal crystallographic orientation on the strength of single-crystal cooled turbine rotor blades is studied. The effect of the cooling system features on the rational choice of the azimuthal crystallographic orientation of modern single-crystal cooled turbine rotor blades is shown. The improvement in the structure and cooling systems of single-crystal cooled turbine rotor blades makes it possible to reduce the influence of the azimuthal crystallographic orientation on their stress state.