bluuebunny/crossref_metadata_2025_split huggingface dataset:
A probabilistic model of fracture of the composite material of a composite overwrapped pressure vessel
Authors: Eremin N V , Moskvichev V V 
Published: January 2020

Abstract
A probabilistic numerical model for fracture of unidirectional composite materials is developed. The algorithm for numerical simulation of the model takes into account the random distribution of carbon fibers, the spread of mechanical properties and the fracture of the structural elements of the material. Multivariate numerical experiments of the composite material of a composite overwrapped pressure vessel under tensile loads were carried out. The analysis of the patterns of deformation and fracture of a composite material is carried out. The physical mechanism of deformation and fracture of a composite material corresponds to a numerical model. The stress-strain curves of a numerical model of a composite material at 70% carbon fiber content are presented. The calculated values of Young’s modulus and tensile strength of the composite material at different percentages are obtained. A comparative analysis of experimental and numerical results showed that the results corresponded to 15%. Using of a numerical model of deformation and fracture of unidirectional composite materials makes it possible to track the mechanics of the processes of fracture of fibers and matrix, to obtain the most accurate analysis of the stress-strain state, and to develop generalized methods for calculating the strength of composite overwrapped pressure vessels
Regularities of destruction of glass tube during compression
Authors: Ermishkin V A , Kulagin S P , Minina N A , Tomenko A K 
Published: January 2020

Abstract
The work is devoted to the study of patterns of destruction of glass tubes. During the study of specimen deformation by compression, a video was taken, the results of which were analyzed by photometric analysis of structural images. Studies have revealed a phenomenological picture of the deformation behavior of glass tube products.
Strength of welded connections of glass and metal
Authors: Ermishkin V A , Kulagin S P , Minina N A , Tomenko A K 
Published: January 2020

Abstract
The purpose of this study was to study the strength of products, which was a structure made of a glass tube, to which molybdenum fringes were welded to the ends. Simultaneously with the deformation on the Instron-3382 testing machine, a video survey of the surface of the samples was carried out, which was analyzed by photometric analysis of structural images. It was shown that the product is elastically deformed and that the presence of edging reduces the structural strength of the product.
On the theory of scale structural fatigue of metals at the proportional loading
Authors: Zavoychinskaya E B 
Published: January 2020

Abstract
The probabilistic multi-level model of metal fatigue at proportional loadings is presented. A system of hypotheses about the step-by-step grow of metal defects on micro-, meso- and macroscale levels is formulated. Here are proposed constitutive relations for the failure probability and a system of fatigue curves and equations of multilevel damage. The amplitude of the maximum principal stress is chosen as a variable, the material functions are determined according to fatigue tests, taking into account the results of physical research of brittle crack grow and in accordance with experimentally valid criteria of fatigue strength. It is shown the correlation between predicted fatigue strength and experimental data for steel 12XH2A, S135 and some ductile steel at combined tension and torsion.
Study of the kinetics of spark plasma sintering of ultrafine-grained hard alloys WC-10%Co
Authors: Lantsev E A , Chuvil’deev V N , Nokhrin A V , Boldin M S , Malekhonova N V , Blagoveshchenskii Y V , Isaeva N V , Tsvetkov Y V , Andreev P V , Smetanina K E 
Published: January 2020

Abstract
The effect of carbon on the kinetics of spark plasma sintering (SPS) of submicron powder compositions WC-10wt.%Co is investigated. Free carbon in the form of graphite was added into submicron powders by mixing. The activation energy of solid-phase sintering under the conditions of isothermal hold and continuous heating rate sintering was determined. It was shown that an increase in the carbon content leads to a decrease in the volume fraction of particles of the η-phase and a shift of the shrinkage curve to the region of lower heating temperatures. It was established that an increase in the graphite content does not significantly affect the activation energy of sintering of submicron powders in the region of “average” heating temperatures, the value of which is close to the activation energy of grain boundary diffusion in cobalt. It has been shown that an increase in graphite content leads to a significant decrease in the activation energy of compaction of WC-Co powders in the region of “high” sintering temperatures due to a decrease in the concentration of tungsten atoms in the γ phase based on cobalt. The kinetics of sintering of fine-grained WC-Co hard alloys is limited by the intensity of the cobalt diffusion creep by Coble.
New method of the estimation of the bending strength of ultrafine-grained structural ceramics for application in the conditions of multiaxial stress-strain state
Authors: Popov A A , Berendeev N N , Boldin M S , Nokhrin A V , Chuvil’deev V N 
Published: January 2020

Abstract
A new method of mechanical testing of high-strength ultrafine-grained ceramic materials by the method of spark plasma sintering (SPS) is proposed. A promising scheme for testing cylindrical SPS-samples is the “Ball on three balls test” (B3B) scheme. The B3B test method has advantages over the standard four-point bending test method, since it is not necessary to cut standard samples from disks, cylindrical samples are aligned on a special support. In this paper, we present a methodology for processing experimental B3B test data developed using the finite element method. The finite element method for estimating the parameters allows us to consider a larger number of parameters that affect the absolute value of the maximum principal stress. The experimental data processing technique takes into account the influence of the sample size, equipment geometry, physical and mechanical properties of the material, and friction coefficient.
Obtaining two-layered pipes and rods using explosion energy and hot deformation
Authors: Yu Malakhov A , Saikov I V , Denisov I V , Cherezov N P , Gamin Yu V , Romantsev B A 
Published: January 2020

Abstract
In this work, experimental studies were carried out to obtain bimetallic pipes and rods using explosion welding and hot deformation. The cladding layer was made of 08Cr18Ni10Ti stainless steel. It was found that explosion welding provides high-quality adhesion of the bimetal layers. Subsequent hot plastic deformation did not affect the ratio of the component layer thicknesses and the quality of the welded joint, which is confirmed by studies of the microstructure and mechanical tests of samples for flattening. Based on the results obtained, a combined technology for the production of bimetallic pipes and rods with a combination of layers of steel 20 + 08Cr18Ni10Ti was developed and tested.
The effect of cyclic deformation on the mechanical, elastic and acoustic characteristics of austenitic stainless steel
Authors: Mishakin V V , Gonchar A V , Klyushnikov V A , Serebryany V N 
Published: January 2020

Abstract
The effect of elastoplastic cyclic straining on the elastic and acoustic characteristics of austenitic stainless steel AISI 321 is investigated. A change of the elastic characteristics of austenitic stainless steel associated primarily with martensitic transformations that affect the accumulated energy density is found. The influence of the amplitude of strain cycle on development of the elastic anisotropy is analyzed. The possibility of determining the stress amplitude of the fatigue loading cycle by an acoustic method involving measuring the elastic characteristic of the material has been demonstrated. The relationship between changes of elastic characteristics and damage is suggested; it can be used for evaluation of fatigue life by the acoustic method.
Determination of nanocharacteristics of strength of structural materials based on signal recording and simulation of time dependences of acoustic emission parameters
Authors: Nosov V V , Grigorev E V , Pavlenko I A 
Published: January 2020

Abstract
Non-destructive testing of the strength of structural materials and products from them is currently based on the correlation between the strength characteristics of the material in a real object and the results of laboratory tests of the strength of standard macro samples. The strength properties and conditions of control’s heterogeneity of different material’s zones of a complex real object make this correlation ambiguous, introducing uncertainty in the results of control. The solution of the problem is connected with the necessity of information transfer to the micro-and nano-level control that determines the strength, the universal physical nanoconstants and the applying of representative micro structural elements of the material as reference. The selection’s principles of these elements and the method of assessing their strength characteristics are considered on the basis of information filtering the results of recording acoustic emission signals (AE) and the micro mechanical model of its parameters.
Room-temperature coefficient of thermal expansion of metals derived from the elastic constants
Authors: Palii N A , Belousov O K 
Published: January 2020

Abstract
Room-temperature coefficients of thermal expansion (CTE), α, of 27 metals and 2 semi-metals (Si and Ge) are derived from elastic constants (Young modulus, shear modulus, Poisson’s ratio) coupled with a Debye treatment of the vibrating lattice. Theoretical values of αcalc show good agreement with the experimental ones.
Structure and Mechanical Properties of the Aluminum Alloy 1570C after Multidirectional Forging with Decreasing Temperature and Subsequent Rolling
Authors: Sh Sitdikov O , Avtokratova E V , Ilyasov R R , Markushev M V 
Published: January 2020

Abstract
The effect of multidirectional forging (MDF) with decreasing temperature and subsequent warm and cold rolling on the structure and mechanical behavior of the alloy 1570C (Al-5Mg-0.18Mn-0.2Sc-0.02Zr (wt.%)) was studied. The first MDF step was carried out at a temperature of 325°C to a strain of about 12 and the second step at 250°C to the strain of about 6. Subsequent rolling was performed in isothermal conditions at the appropriate MDF temperatures, as well as at room temperature with reductions of about 80%. The best complex of service and technological properties, involving data on the parameters of strength, plasticity, superplasticity, was obtained in sheets rolled from high-temperature MDF billet. Despite the more significant grain refinement and unique strengthening, the MDF temperature decrease led to almost complete degradation of superplastic properties. The nature of the alloy behavior found was discussed in detail.
Physical and mechanical properties and structure of copper-based composite materials for diamond tools binder
Authors: Smirnov V M , Shalunov E P , Golyushov I S 
Published: January 2020

Abstract
The article describes the structure and physical and mechanical properties of dispersion-strengthened composite materials of Cu-Al-Ti-Sn-C-O system developed as a binder for making diamond tools for grinding composite materials and, in particular, hard alloys. It is shown that the materials under analysis have high thermal conductivity and recrystallization temperature values and are not inferior by mechanical properties to Cu-Sn system binders and, in particular, Cu-20 Sn binder widely used in the industry.
Quantum-mechanical calculations of the concentration dependence of the total energy of sigma-phase of the Fe-V system for the ground state
Authors: Kupavtsev M V , Udovsky A L 
Published: January 2020

Abstract
The purpose of this work is to study the region of existence of the sigma phase of the Fe-V system. The original algorithm for finding the minimum total energy was developed and tested depending on two independent variables. The optimized values of the lattice parameters for the σ-phase alloys of the Fe-V system are calculated. Dependence of the mixing energy of the σ - phase as a function of the composition x (V) of the sigma - phase of the Fe-V system was obtained. The calculations were carried out using the license package of quantum-mechanical calculations WIEN2k.
Study of the structure of mixed Zr-Y-O and Zr-Y-Mg-O oxides by XRD and XAFS methods
Authors: Moroz E M , Zyuzin D A , Kriventsov V V , Udovsky A L , Saenko I S 
Published: January 2020

Abstract
A comparative study was carried out of the structure of samples of zirconium oxides modified by yttrium and magnesium, synthesized by coprecipitation and calcined during 10 days at a temperature of 1250 °C. Refinement of the structure of the samples according to diffraction data within the framework of the fluorite type, gives high uncertainty factors, regardless of composition, and variation of structural parameters does not reduce their value. EXAFS analysis of the local structure of the samples revealed separate clusters consisting only of yttrium and oxygen ions in the structure of both samples. It has been suggested that the presence of these clusters prevents refinement of structures using the model of statistical solid solution with a fluorite structure.
Quantum-mechanical calculations of the difference of structural energies C14 and bcc phases C14 Fe and Mo and formation energy of ferromagnetic C14 Fe2Mo Laves phase
Authors: Vasilyev D A , Udovsky A L 
Published: January 2020

Abstract
The structural energies of iron and molybdenum in the BCC and C14 Laves phases in the Fe – Mo system, formation enthalpies and bulk elastic moduli are calculated for further use in the calculations of the BCC / BCC+C14Fe2Mo Laves phase boundary at low (room) temperatures.
Design parameters of heat exchange equipment optimization
Authors: Fesenko T N , Shitova L I , Dronova E A 
Published: January 2020

Abstract
The dynamics of straight tubes bundles in heat exchangers, in cross flow of coolant, is considered. The proposed mathematical model allows to determine quantity values which are fundamental in assessing the wear vibration intensity in contact points of tubes with intermediate supports taking into account gap values between tube and support. Tube vibration data obtained by application of this mathematical model (sliding path, contact tubes load in gaps, strain, response frequency structure) allow optimization of design parameters (gaps in intermediate supports, supports number and their location along the tubes length) and operational parameters of heat exchange equipment.
Dispersion methods of preparation of nanosized biological agents for vegetable crops
Authors: Folmanis G E , Fedotov M A 
Published: January 2020

Abstract
The effect of iron and selenium colloidal solutions on seeds was studied. The obtained results showed a different reaction of plants to treatment with solutions of nanosized iron and selenium. Onion seeds in both cases showed low germination – 15%. Colloidal iron treatment showed 100% germination of zucchini and radish seeds as in control, but an iron concentration of 10 mg/l inhibits plants. The greatest root length for beets, cucumbers and carrots was noted at a dose of nanosized iron of 1 mg/l. The root length in the experimental and control samples of zucchini and radish do not differ within the error limits. An increase in seed germination during treatment with nanosized selenium compared with the control samples was observed in onions, carrots, cucumbers, turnips, pumpkins and clarkia. Seed germination of aster was 15%, while in the control sample germination was absent. Nanopowders stimulate the processes of adaptation and self-organization of biological systems and reduce the negative impact of adverse environmental factors.
The control features of thermal characteristic details from alloy with shape memory effect
Authors: Khasyanova D U 
Published: January 2020

Abstract
In the article shows the properties of alloys based TINI with shape memory effects and superelasticity. For high-quality application of such properties of the alloy and the operating conditions, it is necessary to carry out a comprehensive control of thermomechanical characteristics. Therefore, it is necessary to make a standard control, carried out before the launch of a batch of material, and control of phase transformation temperatures for each billet. The article presents the control principles of thermomechanical characteristics of the workpiece material for their using in various operating conditions.
The effect of low temperatures on the operability of products 20GL steel
Authors: Khlybov A A , Kabaldin Yu G , Anosov M S , Ryabov D A , Naumov V I , Sentyureva V I 
Published: January 2020

Abstract
The influence of low temperatures on the cold brittleness of 20GL steel is considered. Tests were carried out on the impact strength of samples of 20GL steel in the temperature range from t = - 60 ° C to a temperature of t = 20 ° C. Fractographic studies of fractures were carried out using optical and electron microscopy. The studies were carried out after normalization, as well as after thermocyclic treatment. The research results showed that thermocyclic treatment leads to an increase in strength characteristics, grain refinement. At the same time, the temperature of the brittle-viscous transition is slightly shifted to the region of positive temperatures.
Hard carbon coatings antifriction properties improvement by alloying
Authors: Buyanovskii I A , Khrushchov M M , Levchenko V A 
Published: January 2020

Abstract
The efficiency of hard carbon coatings with different structure to improve the tribological performance of contacting surfaces of machine parts working in heavily loaded conditions has been analyzed. The possibility of increasing the antifriction and wear-resistant characteristics of these coatings by doping them with metals of the chromium subgroup of the Periodic table has been demonstrated. The possible mechanisms of hard carbon coatings dry and boundary friction tribological properties improvement by alloying have been considered. The possible role of alloying elements choice, structural and tribochemical factors has been discussed.
Research of the metals elasticoplastic cyclic deformation process at reduced temperature
Authors: Kabaldin Y G , Khlybov A A , Anosov M S , Shatagin D A 
Published: January 2020

Abstract
In the present work the test results of steel samples 20 and 45 at a temperature 20° C and -30°C when exposed to variable loads are shown. Fractographic studies of breaks were carried out using optical and electron microscopy. A comprehensive analysis of the materials destruction process, based on the analysis of acoustic emission signals, was also conducted. To estimate the damage of metals the algorithm that uses indicators of fractal dimension and informational entropy of the acoustic emission signal is proposed. The research results showed that the characteristics of fractal dimension and information entropy expand and supplement the capabilities of acoustic methods in the problems of evaluating the performance of materials with low-cycle fatigue at low temperatures.
A modified capacitance model of shunt micro switch based on MEMS technology in actuation mode: simulation and analytical study
Authors: Kurmendra  , Kumar Rajesh 
Published: January 2020

Abstract
In this paper, a modified mathematical model for capacitance analysis of micro-electro-mechanical switch based on Agarwal’s Model has been presented. This model is applicable in the condition when the micro-switch is supplied with electrostatic voltages. Effects of perforated structure and fringe field are accounted for accurate capacitance analysis of the micro-switch. The switch parameters such as thickness of dielectric material and actuation voltage for micro switch have also been considered in the present study. The switch is designed and simulated using COMSOL Multiphysics tool and results obtained through simulations have been validated using MATLAB software. It is found that the results obtained by simulation and mathematical model are in agreement closely for the presented study. This model could be used for evaluation of capacitance in downstate of the micro-switch for symmetric structures.
Performance analysis of a modified reduce component count multilevel inverter
Authors: Khodijah S , Ismail Baharuddin , Isa Muzamir , Syahril M , Rohani M N K H 
Published: January 2020

Abstract
Reducing component in circuitry is desirable in many innovations. In multilevel inverter (MLI) perspective, the increasing of switching devices for a higher-level output will significantly increase power losses, thus affected the output harmonic distortion. In this paper, an extended and simplified three-phase reduce component count multilevel inverter (RCCMLI) structure adapted from S. S. Lee, Cascaded Compact-Module Multilevel Inverter (CCM-MLI) is demonstrated and analysed. Symmetrical reduce component structure with H-bridge inverter is considered in this work. For simplification purpose, the current path conduction for reverse current is not demonstrated in this paper. A simulation-based result is presented to observe the performance of RCCMLI with regards to its output voltage harmonic content. Related predetermined parameter values are included in this report. Particularly, this paper verified the aforementioned RCCMLI, but in higher level and three-phase application, which will further improve the pseudo-sinusoidal inverter output as it eliminates the triplens harmonic component compare to single-phase environment. As for the lower order odd harmonics elimination, computational algorithm namely Particle Swarm Optimization (PSO) has been implemented in the RCCMLI control strategy. In comparison to the traditional Cascaded H bridge (CHB), this work finds that employing the switching angle optimization in the proposed RCCMLI produce comparable improvement in minimizing the output voltage harmonic and able to bring the output quality closer to comply with IEEE 519 distortion limit with fewer components and compact size inverter.
Investigation on partial discharge activities in cross-linked polyethene power cable using finite element analysis
Authors: Isa M A M , Rohani M N K H , Rosmi A S , Isa M , Rosle N , Mustafa W A , Daniel I N , Roslan M A 
Published: January 2020

AbstractThe nationwide usage of cross-linked polyethylene (XLPE) for medium to high voltage distribution networks are practically common due to its excellent electrical, thermal and mechanical properties and widely installed through existing network of cable line in Malaysia. However, cable exposures to harsh climates coupled with inadvertent damage throughout installation or transportation are influencing the presence of voids inside the insulation leading to the initiation of partial discharges (PD) in the cable line. Therefore, this study is important to investigate the activities of PD due to the manifestation of voids in XLPE cable and how it affects the physical, electrical and mechanical characteristics of the cable. Analysis has been performed using Finite Element Analysis (FEA) tool to simulate the PD activities in a 2D model of a three (3) core-XLPE insulated armoured sheathed cable (500 mm2, 11 kV) with several placements of voids. The varied placement and radius of voids is very crucial in order to achieve comprehensive analysis. From the obtained result, it has been established that closest the void to the core yielded higher electric field potential. Additionally, it is verified from the simulation that the larger the size of void, the higher the electric field potential consequently increasing the current density inside the void. This simulation and analysis is quite important to provide better insight pertaining to the behaviour of PD in correspond to the presence of voids which will accelerate ageing failure in insulation framework of the XLPE cable.