Materials physics and mechanics

RAR RUS 1-8 Ioffe Institute Bobyl

St. Petersburg, Russia

Peter the Great St. Petersburg Polytechnic University Davydov

St. Petersburg, Russia

Ioffe Institute Konkov

St. Petersburg, Russia

STC Thin Film Technologies in Power Engineering Kochergin

St. Petersburg, Russia

Ioffe Institute Malevsky

St. Petersburg, Russia

Ioffe Institute Nikitin S.E.

St. Petersburg, Russia

Accelerated degradation by mechanical load of HIT solar cells encapsulated in flexible plastic The degradation of plastic-encapsulated silicon HIT solar cells (156 × 156 mm2) with Ag and Cu metallization was studied under mechanical load with a soft rod with a radius of 25 mm (Ball-on-Ring) up to a maximum 400 kPa. Local 2D photo- and electroluminescence, as well as measurements of dark and light current-voltage characteristics were used. Three phases were detected: (1) an increase in power by 2 – 4 % due to a decrease in leakage currents with pressures up to 125 kPa, (2) accumulation of deformations completed by the avalanche-like formation of a volumetric defect in the substrate with a radius of up to 10 µm with a drop in power by 3 – 5 %, (3) formation of a system of cracks with a width of 10.18149/MPM.5242024_1 accelerated degradation mechanical load avalanche-like crack photoluminescence electroluminescence https://mpm.spbstu.ru/article/2024.103.1/ 1-Bobyl-et-al.pdf

RAR RUS 9-22 Alferov University Komarevtsev

St. Petersburg, Russia

Peter the Great St. Petersburg Polytechnic University Kondrateva

St. Petersburg, Russia

Alferov University Kazakin

St. Petersburg, Russia

Alferov University Enns

St. Petersburg, Russia

Peter the Great St. Petersburg Polytechnic University Lazdin

St. Petersburg, Russia

Peter the Great St. Petersburg Polytechnic University Karaseov

St. Petersburg, Russia

Peter the Great St. Petersburg Polytechnic University Akulshin

St. Petersburg, Russia

MEMS gas sensor of resistive type for detection of hydrogen sulfide down to low concentrations The technological route to manufacture a resistive-type MEMS gas sensor for low analyte concentration detection is proposed and the main characteristics of the device are demonstrated. MEMS consists of a silicon substrate with nickel interdigital electrodes acting as a microheater, on top of which a thin (100 nm) gas-sensitive layer of nickel oxide (NiO) is deposited. The silicon substrate is etched from the back side of the device to achieve a membrane of about 50 microns. The operating temperature of the sensitive layer in measurement mode is 130–205 °C. The proposed device shows the effect of introducing hydrogen sulfide in a gas mixture from 1 to 100 ppm on the conductivity of the sensing layer. http://dx.doi.org/10.18149/MPM.5242024_2 microelectromechanical system nickel oxide microelectromechanical resistive gas sensor hydrogen sulfide https://mpm.spbstu.ru/article/2024.103.2/ 2-Komarevtsev-et-al.pdf

RAR RUS 23-32 S.S.V. College, Hapur (C.C.S. University, Meerut) Kumar

India

Subharti Polytechnic College, Swami Vivekanand Subharti University Kumar

Meerut, Uttar Pradesh, India

K.V. Subharti Сollege of Science Swami Vivekanand Subharti University Kumar

Meerut, India

Mahamaya Government Degree College Kumar

Sherkot, Bijnore, India

CCS University Meerut Nautiyal

Uttar Pradesh, India

Bahauddin Zakariya University Iram

Multan, Pakistan

First-principles investigations of physical properties of Nd doped FeSi compound The structural, electronic, magnetic and thermodynamics properties of the NdFeSi intermetallic compound are studied using the full potential linearized augmented plane wave plus local orbital method, which is based on the theoretical framework of the density functional theory. We calculated the structural properties, in terms of the lattice constant, bulk modulus, first derivative of bulk modulus, and minimum volume. We calculated the electronic properties by considering the band structure, as well as the total and partial density of states. Electronic properties are confirmation that the NdFeSi intermetallic compound exhibits a metallic nature due to Nd-f state. The magnetic properties correlate with the magnetic moment. We determined that this compound's magnetic moment is 7.02610 µB. We investigated thermal behavior in terms of the Grüneisen parameter γ, the bulk modulus B0, the Debye temperature θD, and the entropy S with different temperatures and pressure ranges. All these results indicate that the NdFeSi compound is used in spintronic applications. 10.18149/MPM.5242024_3 DFT electronic properties density of state rare earth element https://mpm.spbstu.ru/article/2024.103.3/ 3-Aman-Kumar.pdf

RAR RUS 33-40 Ufa University of Science and Technology Galeev

Ufa, Russia

Ufa University of Science and Technology Mullayanov

Ufa, Russia

Ufa University of Science and Technology Musin

Ufa, Russia

Ufa University of Science and Technology Kovaleva

Ufa, Russia

The influence of low frequency electric field on the coalescence of water drops in emulsion shear flow Crude oil often mixes with water to form water-in-oil emulsions as a result of factors such as high shear at the production wellhead and surfactants that are naturally present in crude oil. The present study is aimed at determining the conditions leading to electrocoalescence of water droplets in the flow of the emulsion. An important part of this preliminary work concerns the creation of an experimental cell and installation designed to study the massive coalescence of droplets in a shear flow of an emulsion under the action of an applied inhomogeneous alternating electric field. The flow of the emulsion through the cell is created by a syringe pump. We determine the effect of exposure by the volume of the separated phases of the emulsion in the drainage tank. Further research will be related to the study of various emulsions with varying concentration and flow rate and possibly the frequency of the applied field. The research results will be useful for creating devices for electrocoalescence in the flow. 10.18149/MPM.5242024_4 electrocoalescence nonuniform electric field ITO glass photolitography https://mpm.spbstu.ru/article/2024.103.4/ 4-Galeev-et-al.pdf

RAR RUS 41-51 Dr. B.C. Roy Engineering College Ranjan

Durgapur, India

National Institute of Technology Das

Patna, India

Surface modification by laser cladding: state-of-the-art and future prospects Laser surface modification is an advanced technique utilized for the creation of robust coatings on substrates by melting and fusing pre-placed or blown powder materials. In some instances, multiple coatings are applied to achieve intricate geometries. This method serves the purpose of enhancing substrate surface properties and rectifying surface imperfections. Over the past three decades, laser surface modification has garnered significant attention due to its capacity to process a wide range of materials, because of its high energy density and rapid cooling capabilities. Researchers have extensively explored scientific aspects, including the clad-substrate inter-face, microstructure, chemical composition, mechanical properties, and tribological characteristics of deposited materials, as well as their practical applications. This article primarily focuses on the application of laser surface modification to various substrates using suitable cladding materials. Furthermore, it delves into the survey of modification parameters, such as microstructural refinement, mechanical attributes, and tribological performance, as investigated by previous scholars. Additionally, this article presents the findings of past research endeavors and offers insights into potential avenues for future investigations within the realm of laser surface modification. 10.18149/MPM.5242024_5 surface modification laser cladding microstructure microhardness tribological properties https://mpm.spbstu.ru/article/2024.103.5/ 5-Rajeev-Ranjan%2C-Anil-Kumar-Das.pdf

RAR RUS 52-62 Peter the Great St. Petersburg Polytechnic University Syundyukov

St. Petersburg, Russia

Peter the Great St. Petersburg Polytechnic University Skotnikova

St.Petersburg, Russia

Peter the Great St. Petersburg Polytechnic University Ryabikin A.Yu.

St. Petersburg, Russia

Ultrasonic layer-by-layer treatment of PN85Y15 coating as a way to increase wear resistance of friction pair with bronze Tribotechnical tests on wear resistance of friction pairs "coating PN85Y15 - bronze BrB2", at loads of 100 and 300 N, sample rotation speed of 300 rpm, with lubricant Lukoil Luxe 5W40 have been carried out. It is shown that the plasma coating applied to steel 45 together with layer-by-layer ultrasonic treatment (UST) with the power of 200 W, in comparison with the coating with UST with the power of 400 W and without UST, had a higher adhesion to the base metal and sufficient porosity, which working with lubricant provided the crankshaft with increased lubricity, formation of favourable compressive residual stresses, formation in the coating of a two-component structure of large (~40 μm) granules and small (~1–7 μm) superhard intermetallic particles of phases Fe2Al5, which filled surface imperfections and reduced the coating roughness by 2 times, reduced the friction coefficient by 2 times, weight wear by 12 times and contact temperature by an average of 5 °C. 10.18149/MPM.5242024_6 plasma spraying tribotechnical tests ultrasonic treatment surface roughness friction coefficient contact temperature https://mpm.spbstu.ru/article/2024.103.6/ 6-Syundyukov.pdf

RAR RUS 63-80 Institute for Problems in Mechanical Engineering of RAS Sedakova

St. Petersburg, Russia

Ioffe Institute Pozdnyakov

St.Petersburg, Russia

Thermal analysis of wear of polymer-polymer friction pairs in vacuum and atmosphere conditions A study of friction and wear of polyoxymethylene-polyoxymethylene and polytetrafluoroethylene-polytetrafluoroethylene pairs with simultaneous registration of the level of heating caused by friction has been carried out. The data obtained were analyzed both by using the energetic wear versus friction power plots and by using the solutions of finite element simulations of the thermal problem in the realistic friction geometry of the thrust bearing type used in the experiments. The solutions provide estimates of heating in vacuum and atmosphere. The calculated heating levels in vacuum suggest that triboinduced scissions of polyoxymethylene macromolecules registered by means of mass-spectrometry in polyoxymethylene-polyoxymethylene pair are initiated at temperatures below the temperatures of the onset of pure thermal decomposition of this polymer and its melting. Correlation between the presence of triboinduced scissions of macromolecules upon friction force transition, the registered exponential growth of wear upon increase of friction power in polyoxymethylene-polyoxymethylene pair and the absence of these phenomena in other pairs studied suggests that triboinduced scissions of macromolecules is governing mechanism controlling overall wear of the polymers studied. The approach was also shown to be informative in comparison of the wear of these polymers against steel and of the wear of pure polyoxymethylene and its composite with C60 fullerene. 10.18149/MPM.5242024_7 Polymer polymer composite sliding surface temperature friction pair friction force friction work wear resistance vacuum convection mass-spectrometry plastic deformations polyoxymethylene polytetrafluoroethylene https://mpm.spbstu.ru/article/2024.103.7/ 7-Pozdnyakov%2C-Sedakova-.pdf

RAR RUS 81-90 Institute of Molecule and Crystal Physics of the Ufa Federal Research Center of the Russian Academy of Sciences Aksenov

Ufa, Russia

Institute of Molecule and Crystal Physics of the Ufa Federal Research Center of the Russian Academy of Sciences Shishkunova

Ufa, Russia

Institute of Molecule and Crystal Physics of the Ufa Federal Research Center of the Russian Academy of Sciences Asfandiyarov

Ufa, Russia

Institute of Molecule and Crystal Physics of the Ufa Federal Research Center of the Russian Academy of Sciences Sementeeva

Ufa, Russia

Structure and strength of Mg-Zn-Zr alloy subjected to high pressure torsion Magnesium alloys are considered a promising material for the production of biodegradable implants. However, their widespread adoption is hindered by their low strength and high corrosion rate. Deformation can enhance the strength characteristics; however, due to the limited number of slip planes in magnesium alloys, choosing the deformation processing regime for them is a non-trivial task. This study presents the results of research aimed at determining the influence of processing modes by high-pressure torsion on the transformation mechanisms of the structure and mechanical characteristics of the Mg-8.6Zn-1.2Zr alloy. It is shown that at room temperature, predominantly a twinning structure is formed, with microhardness values reaching 1200 MPa. However, it is demonstrated that such a structure leads to significant embrittlement of the Mg-8.6Zn-1.2Zr alloy. Deformation at a temperature of 250 °C leads to the formation of recrystallized grains with a size of 3–4 μm. After 5 revolutions of high-pressure torsion, the microhardness is 820 MPa, and the tensile strength is 335 MPa, with an elongation of 13 %. 10.18149/MPM.5242024_8 magnesium alloys biomedical applications severe plastic deformation bioresorbable materials nanomaterials https://mpm.spbstu.ru/article/2024.103.8/ 8-Aksenov(1).pdf

RAR RUS 91-99 St. Petersburg State University Volkov A.E.

St. Petersburg, Russia

Institute for Problems of Mechanical Engineering RAS Belyaev F.S.

St. Petersburg, Russia

Saint Petersburg State University Volkova

St. Petersburg, Russia

Saint Petersburg State University Vukolov

St. Petersburg, Russia

St. Petersburg State University Evard M.E.

St. Petersburg, Russia

St. Petersburg State University Rebrov

St. Petersburg, Russia

The effect of martensite stabilization in titanium nickelide after various methods of pre-deformation: simulation with a single set of constants Design of shape memory alloy sensors and actuators requires taking into account the martensite stabilization effect, which consists in a shift upward of the reverse martensitic transformation temperatures after preliminary deformation. In this work it is assumed that this effect is due to damage in martensite domain boundaries during pre-straining. This idea is accounted for in a microstructural model by introducing a variable for boundaries damage and formulating evolution equations. The reverse transformation temperature shift is described with one set of constants for three pre-straining modes: deformation of a specimen in the martensitic state, cooling under a constant stress, and deformation in the austenitic state inducing martensite by stress. For Ti50Ni50 and Ti49Ni51 (at. %), the model matches experimental data well for the first two modes and qualitatively for the third. 10.18149/MPM.5242024_9 shape memory alloys titanium-nickel martensite stabilization modeling microstructural model https://mpm.spbstu.ru/article/2024.103.9/ 9-Volkov-et-al.pdf

RAR RUS 100-113 Centre Universitaire Nour Bachir El-Bayadh Mokaddem

El Bayadh, Algeria

Centre Universitaire Nour Bachir El-Bayadh Belkheir

El Bayadh, Algeria

Centre Universitaire Nour Bachir El-Bayadh Rouissat

El Bayadh, Algeria

Centre Universitaire Nour Bachir El-Bayadh Doumi

El Bayadh, Algeria

Université des Sciences et de la Technologie d’Oran Mohamed-Boudiaf Boutaous

Oran, Algeria

Interface shear damage of novel biocomposite materials based on polyhydroxyalkanoates biopolymer matrix Bioplastics reinforced with natural fibers are gaining attention for their potential in various emerging eco-friendly applications, resulting in new materials with exceptional mechanical and thermal properties. This study examines PHA biopolymer plastic as a polymer matrix for natural fibers, specifically date palm, coconut, and sisal. It focuses on calculating shear damage at the fiber-matrix interface for the biocomposites date palm/PHAs, coconut/PHAs, and sisal/PHAs. The results show that under mechanical stresses (σ = 40, 45, 50, and 55 MPa), damage levels increase due to the accumulation of stresses, with sisal/PHAs exhibiting more severe degradation at the interface compared to date palm/PHAs and coconut/PHAs. These findings highlight the significant role of natural fibers in enhancing the mechanical properties of composite materials. 10.18149/MPM.5242024_10 bioploymers PHA natural fibers date palm coconut sisal https://mpm.spbstu.ru/article/2024.103.10/ 10-Allel-Mokaddem.pdf

RAR RUS 114-140 0000-0002-9212-2579 Lomonosov Moscow State University Khokhlov Andrew

Moscow, Russia

Hybrid of a nonlinear Maxwell-type viscoelastoplastic model with the linear viscoelasticity constitutive constitutive equation and properties of crossbred creep and stress-strain curves A generalization for the physically nonlinear Maxwell-type constitutive equation is proposed with two material functions for non-aging rheonomic materials, which have been studied analytically in previous articles to elucidate its properties and application. To extend the set of basic rheological phenomena that it simulates, we propose to add the third strain component expressed as the Boltzmann-Volterra linear integral operator governed by an arbitrary creep function. To generalize and conveniently tune the constitutive relation, to fit it to various materials and various lists of phenomena (test data), we introduce a weighting factor (i.e. nonlinearity factor) into the equation. This allows us to crossbreed primary physically nonlinear Maxwell-type model with the linear viscoelasticity equation in an arbitrary proportion, to construct a hybrid model and to regulate prominence of different phenomena described by the two constitutive equations we crossbred. General expression for stress-strain curves at constant stress rate and for the creep and recovery curves families obtained using the proposed hybrid constitutive equation are derived and analyzed. The basic properties of the stress-strain curves and the creep-recovery curves are studied assuming three material functions are arbitrary. They are also compared to the properties obtained using primary Maxwell-type model and linear viscoelasticity theory. New properties are found that allow the hybrid model to tune the form of the stress-strain curves and the creep-recovery curves and to simulate additional effects observed in constant stress rate tests and creep-recovery tests of various materials at different stress rates and stress levels. 10.18149/MPM.5242024_11 viscoplasticity viscoelasticity creep physical non-linearity material functions stress-strain curves family stress rate sensitivity equilibrium stress-strain curve creep-recovery curves applicability indicators https://mpm.spbstu.ru/article/2024.103.11/ 11-Khokhlov.pdf

RAR RUS 141-151 Ecole Nationale Polytechnique d'Oran Ouadah

Oran, Algérie

Ecole Nationale Polytechnique d'Oran Maurice AUDIN Hamdadou

Oran, Algeria

Synthesis of WO2.72:Fe thin films via ammonium tungstate precursor by spray pyrolysis technique and annealing In this study, WO2.72:Fe thin films have been prepared on glass substrates heated to a fixed temperature of 350 °C by the spray pyrolysis technique, from an aqueous ammonium tungstate solution (NH4)10H2(W2O7)6 with a concentration of 0.005 M. The dopant concentrations were 1, 3 and 5 %. After deposition, the thin films were annealed at 550 °C for 4 h. The characterization results revealed that Fe doping has a significant effect on the morphology of thin films depending on its concentration. In addition, it promotes crystallites growth and improves the surface quality. GIXRD analysis has shown that the thin films obtained after the annealing are polycrystalline in nature, the structure of the WO2.72 films was monoclinic, with space groups P2/m (10). The growth direction was variable depending on the doping concentration. It was noticed that the peaks positions, the preferential grain orientation and the structural parameters are affected by the doping concentrations, which had no effect on the phase type of the obtained films. The WO2.72 films have interesting optical properties; high transmittance in the visible range of 75 % as well as high absorption in the ultra-violet range from 1.4 to 0.2 a.u. Moreover, the films exhibit both direct and indirect electronic transitions, which are red-shifted due to Fe-doping. 10.18149/MPM.5242024_12 WO2.72 thin film spray pyrolysis Fe-doping roughness GIXRD spectrophotometry https://mpm.spbstu.ru/article/2024.103.12/ 12--Ouadah-%2C-Hamdadou.pdf

RAR RUS 152-162 National Research Moscow State University of Civil Engineering Fedosov

Moscow, Russia

Ivanovo Fire and Rescue Academy Lazarev

Ivanovo, Russia

Ivanovo Fire and Rescue Academy Maltsev

Ivanovo, Russia

Ivanovo State Polytechnic University Toropova

Ivanovo, Russia

Ivanovo Fire and Rescue Academy Bogdanov

Ivanovo, Russia

Fiberglass thermal barrier for building safety The state of the issue of fire protection from landscape fires is studied and discussed. We set tasks to evaluate the recovered samples of two rolled fiberglass systems by modifying them in various ways: "fiberglass + refractory foam" and "fiberglass + aluminum foil". The first method involves applying a single layer of refractory foam Penosil Premium to the exposed surface of the samples. The second method is to modify the exposed surface by wrapping a layer of aluminum foil. The possibility of resisting an impacting landscape fire with a certain heat flux density was studied. We described the methods of conducting bench tests of a difficult-to-burn material under the influence of a constant heat flow, determine the temperature change of fiberglass from the heating time of the samples, the loss of their mass, determine the reliability of the empirically obtained data. A method for restoring a protective barrier made of fiberglass after damage by a landscape fire is proposed. At the same time, the temperature of the back side of the samples recovered using aluminum foil is reduced by half in relation to samples with refractory foam on the surface and is 173.2 °C (with the application of a single layer of foam 337.1 °C). 10.18149/MPM.5242024_13 landscape fire protective barrier weakly combustible fiberglass bench tests https://mpm.spbstu.ru/article/2024.103.13/ 13-Fedosov-et-al.pdf

RAR RUS 163-172 RTM Nagpur University Lamba

India

Quasi-static thermal response of a circular plate due to the influence of memory-dependent derivatives In this paper, the thermal deformation response of a circular plate due to the influence of memory-dependent derivatives (MDD) is analyzed using a quasi-static approach. The top, bottom, and curved surfaces of the plate experience convective boundaries with heat flow on the outer curved radii, and additional cross-sectional heating is prescribed on the top and bottom plate surfaces. Integral transformation methods are used to solve the memory-dependent heat transfer model. Due to the complex nature of the analytical analyses, the Laplace transform is numerically inverted. The rate of change in temperature and thermal deflection is dependent on past changes, making it more suitable for studying physical problems. Numerical calculations of the obtained thermal results are performed for a copper plate and presented graphically. 10.18149/MPM.5242024_14 memory-dependent derivatives circular plate temperature thermal deflection integral transform https://mpm.spbstu.ru/article/2024.103.14/ 14-NK-Lamba.pdf

RAR RUS 173-182 Gazprom Neft PJSC Kunakova

St. Petersburg, Russia

Gazpromneft-Orenburg LLC Svintsov

Orenburg, Russian Federation

Gazpromneft-Orenburg LLC Olenev

Orenburg, Russian Federation

Gazprom Neft PJSC Gogolev

St. Petersburg, Russia

Gazprom Neft PJSC Sayfutdinova

St. Petersburg, Russia

Gazprom Neft PJSC Solodovnikova

St. Petersburg, Russia

Comprehensive studies of pipes metal to identify the causes of failure in the gas pipeline of the gas lift system of an oil and gas condensate field The results of a comprehensive study of pipes metal to identify the causes of failure in the gas pipeline of the gas lift system of an oil and gas condensate field transporting gas with a high content of carbon dioxide and hydrogen sulfide are presented. The research program included visual assessment of the pipe surface, metallographic, mechanical, electrochemical tests, determination of the chemical composition of steel and deposits. According to the results of the studies, it was established that the destruction of the pipeline was the result of thinning of the pipeline wall along the upper generatrix with the subsequent appearance of a crack up to the through outlet to the outside. Gas pipelines subjected to corrosion along the upper generatrix require a systematic approach to prevent failures. 10.18149/MPM.5242024_15 studies of pipes metal causes of failure in the gas pipeline corrosion corrosion along the upper generatrix causes of failure analysis gas pipeline top of the line corrosion https://mpm.spbstu.ru/article/2024.103.15/ 15-Kunakova-et-al(1).pdf