Materials physics and mechanics

RAR RUS 1-21 National Institute of Technology Karnataka Mundla S.R.

Surathkal, India

57196120922 0000-0003-4133-5635 Dayananda Sagar University Arungalai Vendan Subbiah

Bangalore, India

Raja Ramana Centre for Advanced Technology Paul C.P.

Indore, India

0000-0003-0273-7746 National Institute of Technology Karnataka Shettigar A.K.

Surathkal, India

National Institute of Technology Karnataka Jambagi S.C.

Surathkal, India

Experimental investigations on the milling characteristics of Cu alloys and additively manufactured CuCrZr Copper is one of the widely used materials in various fields such as automotive, electronics, aviation, etc. The inherent property of copper makes it useful in wide variety of applications. The features on different components using the copper material can be made using different manufacturing techniques. However, post processing is one of the inevitable steps in any manufacturing process. Machining is one of the widely used post processing. There are multiple varieties of milling process. Among them, end milling process is widely used for making the slots. Three important process parameters in end milling process are depth of cut, cutting rate and feed rate. In this experimental approach, the copper is subjected to end milling operation by varying the aforementioned input parameters. In this fast-moving world, any manufacturing industry aims to produce the features with good dimensional accuracy with minimal amount of tool wear. Hence, the output responses selected are surface roughness and the tool wear. This research investigates the machining behavior of pure copper (Cu) and additively produced CuCrZr alloys to assess how fabrication methods affect processability. Pure copper, recognized for exceptional thermal / electrical conductivity, is compared against additively manufactured CuCrZr, which retains copper’s advantages while offering improved strength and wear resistance through alloy composition. During the milling process the following parameters such surface quality, cutting forces, tool degradation, and removal rates are reviewed through proper analysis. Compared to commercial copper, CuCrZr is more difficult to machine because it requires precise control over machining parameters to attain superior surface quality during milling. It is found that the CS and FR parameters balance material removal rate while controlling surface quality in both materials. As–built CuCrZr finds demand in high–performance applications such as heat exchangers, rocket engine components, and electrical contacts wherein strength, excellent thermal conductivity and additive manufacturability are critical. 10.18149/MPM.5342025_1 CuCrZr milling as built surface roughness depth of cut https://mpm.spbstu.ru/article/2025.109.1/ 1_mundla_et_al.pdf

RAR RUS 22-34 0000-0002-0090-5745 RUDN University Hematibahar M.

Moscow, Russia

0000-0002-2773-4114 Moscow State University of Civil Engineering Kharun M.

Moscow, Russia

0000-0002-2279-1240 Far Eastern Federal University Fediuk R.S.

Vladivostok, Russia

0000-0002-1196-8004 Peter the Great St. Petersburg Polytechnic University Vatin N.I.

St.Petersburg, Russia

0009-0001-5160-2357 Perm Military Institute of the National Guard Troops of the Russian Federation Porvadov M.G.

Perm, Russia

Moscow State University of Civil Engineering Sabitov L.S.

Moscow, Russia

Predicting the flexural strength of 3D-printed geopolymer reinforced concrete using machine learning techniques Both geopolymer concrete and 3D printing are innovative trends in construction materials science. This study investigates the prediction of 3D printed geopolymer reinforced concrete due to lack of information and studies on the prediction of 3D printed geopolymer reinforced concrete. This study investigated for the first time the flexural strength of 3D printed reinforced concrete through compressive strength with concrete mix design. Rigid, Lasso, elastic net, random forest, gradient boosting, decision tree, support vector machine regression and k-nearest neighbor are examined in this study. Considering to this study, compressive strength and flexural strength have more than 0.97 relationship. Moreover, the best result was for gradient boosting, random forest and k-nearest neighbor with 0.85 and 0.89. 10.18149/MPM.5342025_2 3D printing concrete 3D printing reinforced concrete auxetic geopolymer prediction https://mpm.spbstu.ru/article/2025.109.2/ 2_fediuk_rs_et_al.pdf

RAR RUS 35-52 0009-0004-2796-3170 Mien Tay Construction University Lam T.Q.K.

Vinh Long, Vietnam

Vinh Long Water Supply Joint Stock Company Nguyen M.T.

Vinh Long, Vietnam

0009-0000-0142-1235 Mien Tay Construction University Lam H.K.

Vinh Long, Vietnam

0000-0002-5140-9725 Jyothy Institute of Technology, Visvesvaraya Technological University Sreekeshava K.S.

Belagavi, India

Structural behavior of reinforced concrete beams incorporating cocopeat as a partial sand replacement This study investigated the reinforced concrete beams’ structural behavior when the sand aggregate is partially replaced with coconut peat also known as cocopeat. The concrete mixes were prepared by 0, 20, 50 and 100 % variation levels of replacement. Flexural loading tests were conducted on the reinforced concrete beams by also considering the variations in stirrup spacing and main bar diameters. The results indicated that, replacement up to 20 % of sand with hardened cocopeat maintained acceptable structural performance with those with 20 % replacement presented a comparable load bearing capacity and crack resistance to control specimen. Greater than 20 % replacement level exhibited significant reduction in strength and stiffness. The results also revealed that closer stirrup spacing, and larger diameter steel bars overcome the limitations of cocopeat content, improving the beam performance. The study supports the potential use of cocopeat as partial sand replacement in sustainable concrete construction. 10.18149/MPM.5342025_3 construction materials cocopea sand content hardening method sand aggregate https://mpm.spbstu.ru/article/2025.109.3/ 3_lam_tqk_et_al.pdf

RAR RUS 53-65 0009-0007-9307-4509 Guru Ghasidas Vishwavidyalaya (Central University) Sahu Y.K.

Bilaspur, India

0000-0001-7028-1272 Guru Ghasidas Vishwavidyalaya (Central University) Arjunan T.V.

Bilaspur, India

0000-0002-2764-7037 Guru Ghasidas Vishwavidyalaya (Central University) Singh S.

Bilaspur, India

Guru Ghasidas Vishwavidyalaya (Central University) Vishwas S.

Bilaspur, India

Experimental investigation and development of sustainable natural fiber based reinforced composite Sustainable development goal is the development of such as materials, which might not drop the negative impact over the environment, ecology and society and has long resiliency or life if bring into use. In today’s era, the world is concentrating on alternative materials that are naturally recyclable and friendly to the environment. In place of synthetic fibres, renewable natural fibres now offer an alternative polymer composite material. Pollution of the environment has become unavoidable due to the toxic gas emissions from burning large quantities of residual rice straw fibres. As we know that natural fiber and epoxy resin is ascertained as momentous composite material amongst other composite materials due to its multipurpose usage in engineering, versatility cum unique mechanical properties, low-cost fabrication, renewable, biodegradable, and recyclable. In the presented research work, analysis of mechanical Behavior, of rice straw and bamboo fiber hybrid composite. To analysis same, in this research work a hybrid composite was created by first treating rice straw fibre with sodium hydroxide in an alkali process and then combining the treated rice straw sheet in stacking sequences with bamboo fiber. The testing results show that the specific tensile strength and flexural strength of rice straw fiber combined with bamboo fiber is greater than another hybrid composite. In addition to that, the hardness of rice straw fiber combined with bamboo fiber is also found greater than the other hybrid composite. The discussed hybrid composite fabrication scheme, testing, analysis and results represented graphically throughout the presented research work. 10.18149/MPM.5342025_4 natural fiber mechanical behavior alkali treatment sustainable material development https://mpm.spbstu.ru/article/2025.109.4/ 4_sahu_et_al.pdf

RAR RUS 66-75 0000-0001-7536-2258 Peter the Great St. Petersburg Polytechnic University Keresten I.A.

St. Petersburg, Russia

0000-0001-8358-7211 St. Petersburg Institute of Technology (Technical University) Pirozhnikov P.B.

St. Petersburg, Russia

0000-0003-0554-4579 Peter the Great St. Petersburg Polytechnic University Suranov I.S.

St. Petersburg, Russia

0000-0002-6259-2019 St. Petersburg Institute of Technology (Technical University) Erofeev D.A.

St. Petersburg, Russia

0000-0003-4698-1484 Institute of Medical Education of Almazov National Medical Research Centre Titov A.G.

St. Petersburg, Russia

Experimental and numerical determination of mechanical properties of porous thermoplastic The main aim of this paper is to experimentally and numerically determine the mechanical properties of thermoplastics that exhibit porosity due to 3D-printing. The mechanical properties of thermoplastics (polyacrylonitrile-co-butadiene-co-styrene, polycarbonate, polyetherimide) were investigated using both tensile testing machine and finite element method. The object of the study is the standard 3D-printed specimen for tensile testing. According to the result of the experimental determination of the stress–strain curves of specimens under partial loading, full unloading and repeated loading, a gradual accumulation of plastic strain was revealed for all considered thermoplastics. A finite element model for testing standard tensile specimens has been developed and validated. As a result of validation, multilinear isotropic hardening material law was identified for all investigated thermoplastics. Measured mechanical properties of porous thermoplastics were compared with properties declared by the manufacturer for the original raw material. 10.18149/MPM.5342025_5 thermoplastics polyacrylonitrile-co-butadiene-co-styrene polycarbonate polyetherimide digital engineering mechanical properties finite element method https://mpm.spbstu.ru/article/2025.109.5/ 5_keresten_ai_et_al.pdf

RAR RUS 76-90 Govt. College Sharma Virender

Tissa, Chamba, Himachal Pradesh, India

Himachal Pradesh University Devi Jyoti

Shimla, India

59122315900 0000-0002-1572-2108 Kurukshetra University Kumar Rajneesh

Kurukshetra, India

Himachal Pradesh University Sharma Veena

Shimla, India

Double diffusive convection of non-Newtonian nanofluid in porous layer under internal heating The onset of double-diffusive convection in a non-Newtonian nanofluid-saturated porous layer is investigated under the effect of internal heating and various boundary conditions. A non-Newtonian nanofluid is modeled using the Buongiorno framework for nanoparticles combined with the Jeffrey model for viscoelastic fluid behavior. The governing coupled differential equations are reduced to ordinary linear differential equations via the normal mode method, the Boussinesq approximation, and linear stability analysis. Eigenvalue problems are solved using realistic boundary conditions to determine the stationary Rayleigh numbers, which describe the initiation of non-oscillatory convection in terms of non-dimensional controlling parameters. This work is motivated by practical applications in geophysics, energy engineering, and materials science, where non-Newtonian nanofluids in porous layers are subjected to internal heating, such as in geothermal reservoirs, enhanced oil recovery, and thermal management systems. The analysis demonstrates that reduced particle density and internal heating promote convection, whereas porosity, solutal Rayleigh number, concentration Rayleigh number, and modified diffusivity ratio stabilize the system. Furthermore, reduced particle density enhances instability, while the Jeffrey parameter introduces viscoelastic effects that weaken stability without altering convection cell size. These findings provide new insights into the stabilization and destabilization mechanisms of nanofluid systems, with implications for designing advanced energy and material processing technologies. 10.18149/MPM.5342025_6 Internal heat source Jeffrey model double diffusive convection porous material https://mpm.spbstu.ru/article/2025.109.6/ 6_sharma_et_al.pdf

RAR RUS 91-98 0000-0002-0448-7624 Ioffe Institute Kharitonskii

St. Petersburg, Russia

0009-0003-3300-8332 St. Petersburg Electrotechnical University "LETI" Ivanov N.A.

St. Petersburg, Russia

0000-0003-4205-3226 Ioffe Institute Guzilova L.I.

St.Petersburg, Russia

0000-0001-6047-1208 St. Petersburg Electrotechnical University "LETI" Gareev K.G.

St. Petersburg, Russia

Landau-Lifshitz-Gilbert equation: magnetization of a superparamagnetic particle ensemble in the mean-field approximation A numerical method for solving the Landau-Lifshitz-Gilbert equation for an ensemble of superparamagnetic nanoparticles within the mean-field approximation is presented. The classical fourth-order Runge-Kutta method is employed for the time integration of the equation. The model simulates an ensemble of uniaxial nanoparticles subjected to a constant external magnetic field. It is shown that the proposed approach accurately reproduces the magnetization dynamics: the components perpendicular to the field decay, while the longitudinal component relaxes toward a steady-state value. The results are qualitatively consistent with previously published data obtained using the Vinamax simulation software. 10.18149/MPM.5342025_07 superparamagnetism diluted magnet Landau-Lifshitz-Gilbert equation mean-field approximation dipole-dipole interaction https://mpm.spbstu.ru/article/2025.109.7/ 7_kharitonskii_pv_et_al.pdf

RAR RUS 99-110 Pryazovskyi State Technical University Burlakov V.I.

Mariupol, Russia

Peter the Great St. Petersburg Polytechnic University Artiukh V.G.

St. Petersburg, Russia

Peter the Great St. Petersburg Polytechnic University Kitaeva D.A.

St.Petersburg, Russia

Peter the Great St. Petersburg Polytechnic University Korihin N.V.

St. Petersburg, Russia

Machinability of nitride ceramics with abrasive powders and their addition to diamond powder Development of modern engineering is related to development and introduction of new materials and progressive technological processes of their treatment. Unique properties of ceramics allow them to be used in various fields of technology, including, as a cutting instrument and the machines, devices, radio and electronic apparatus details. Due to the high hardness of materials, tooling of instrumental purveyances is possible only with synthetic diamonds, but synthetic diamonds are quite expensive there, so it is necessary to solve the problem of replacing expensive materials with cheaper ones. Improvement of ceramics treatment methods is related to study of conformities to law of difficult multivariable process of polishing. Productivity, quality of surface, wear and firmness of instrument, power charges are determined by properties of ceramics, descriptions of diamond instrument, modes and by technological features of equipment. Providing high quality surface at exact ceramic details is a difficult requirement specification. Next to a subzero roughness that is limited to parts of microns, a specific requirement is absence of surface defects (coulisse, miсrocracks, miсrocavities). As ceramic materials are fragile then at loading under act of cutting or polishing instruments of good from them tend to spalling. Point loading during a small enough flowage result in that under act of grains of diamond of ceramics, feeling strong mechanical and thermal loading, painted as a result of it there is a ditch width of that exceeds the area of collision of diamond grain with material. 10.18149/MPM.5342025_8 vibro-magnetic-abrasive processing material removal rate surface roughness СBN ceramics https://mpm.spbstu.ru/article/2025.109.8/ 8_burlakov_vi_et_al.pdf

RAR RUS 111-119 Pryazovskyi State Technical University Dan L.A.

Mariupol, Russia

Pryazovskyi State Technical University Maslov V.A.

Mariupol, Russia

Pryazovskyi State Technical University Trofimova L.A.

Mariupol, Russia

Pryazovskyi State Technical University Kargin S.B.

Mariupol, Russia

Peter the Great St. Petersburg Polytechnic University Artiukh V.G.

St. Petersburg, Russia

Peter the Great St. Petersburg Polytechnic University Kitaeva D.A.

St.Petersburg, Russia

Peter the Great St. Petersburg Polytechnic University Korihin N.V.

St. Petersburg, Russia

About possibility of using the Roginsky-Schulz and Avrami-Erofeev equations in topokinetic analysis of carbothermic self-recovery of dispersed iron-graphite waste Topokinetic analysis of experiment results on carbothermic self-healing of "wustite-graphite" dispersed samples particles was carried out. It was shown a dispersed iron-graphite waste contains metallic iron, iron oxide, carbon and impurities. Observations and calculations made in this work confirmed two-stage nature of process. The first initial stage of the process, at degrees of conversion less than 0.4, can be described by the Roginsky-Schulz or Avrami-Erofeev equations. Apparent activation energy of the initial stage of the process was calculated to be 141.34 kJ/mol. It was found that the Bell-Boudoir reaction is a limiting factor in the process. 10.18149/MPM.5342025_9 topokinetic approach graphite dispersed iron-graphite waste cast iron carbothermic self-healing wustite-graphite https://mpm.spbstu.ru/article/2025.109.9/ 9_dan_la_et_al.pdf

RAR RUS 120-130 0009-0007-5263-3087 Ho Chi Minh City University of Technology and Education Tran Bao Quan

Ho Chi Minh City, Vietnam

0009-0009-5422-867X Ho Chi Minh City University of Technology and Education Ngo Thi Nhu Huynh

Ho Chi Minh City, Vietnam

Nguyen Tat Thanh University Center for Hi-Tech Development Nguyen Khac Binh

Saigon Hi-Tech Park, Ho Chi Minh City, Vietnam

Ho Chi Minh City University of Technology and Education Duong Hong Diu Tho

Ho Chi Minh City, Vietnam

Ho Chi Minh City University of Technology and Education Thach Bao Khang

Ho Chi Minh City, Vietnam

0000-0002-8475-0225 Nguyen Tat Thanh University Center for Hi-Tech Development Pham Hoai Phuong

Saigon Hi-Tech Park, Ho Chi Minh City, Vietnam

0000-0002-6205-0850 Ho Chi Minh City University of Technology and Education Ngo Hai Dang

Ho Chi Minh City, Vietnam

0009-0000-4865-3420 Ho Chi Minh City University of Technology and Education Pham Thi Kim Hang

Ho Chi Minh City, Vietnam

Fabrication and characterization of NiO/AZO heterojunction thin film diodes by radio frequency magnetron sputtering This study focuses on the fabrication and investigation of the properties of the heterojunction p-NiO/n-Al-doped ZnO via the radio frequency magnetron sputtering method. We conducted a detailed evaluation of the crystal structure, optical properties, and electrical properties of the NiO and Al-doped ZnO monolayers using advanced techniques such as X-ray diffraction, ultraviolet-visible spectroscopy, and Hall effect measurements. X-ray diffraction results show that the NiO thin film crystallizes in the (111) and (200) peaks with a characteristic NaCl-type cubic structure, while the Al-doped ZnO thin film preferentially develops in the (002) peak, exhibiting a hexagonal wurtzite structure. UV–Vis transmission spectrum analysis indicates that the NiO and Al-doped ZnO thin films exhibit transmittance rates of 52 and 92 % in the visible light region, respectively. The optical band gap energy was determined to be 3.45 eV for NiO and 3.36 eV for Al-doped ZnO, respectively. In addition, the carrier concentration in both single layers reached a high level, around 1019 cm-3. The J-V characteristics under optimal conditions confirmed the formation of the NiO/AZO heterojunction with a turn-on voltage of 0.67 V, an ideality factor of 4.44, and a barrier potential height of 0.5 eV. Especially, the influence of light with a wavelength of 365 nm, this heterojunction clearly exhibited the characteristics of a photodiode. These results demonstrate the remarkable potential applications of the p-NiO/n-AZO heterojunction in the fields of optoelectronics and light sensors. 10.18149/MPM.5342025_10 Al-doped ZnO NiO photodiode heterojunction RF-magnetron sputtering https://mpm.spbstu.ru/article/2025.109.10/ 10_tran_bq_et_al.pdf

RAR RUS 131-168 0000-0002-9212-2579 Lomonosov Moscow State University Khokhlov Andrew

Moscow, Russia

North-Eastern Federal University Okhlopkova Aitalina

Yakutsk, Russia

North-Eastern Federal University Sleptsova Sardana

Yakutsk, Russia

North-Eastern Federal University Lazareva Nadezhda

Yakutsk, Russia

North-Eastern Federal University Tarasova Praskovia

Yakutsk, Russia

Moscow Aviation Institute (National Research University) Babaytsev Arseny

Moscow, Russia

North-Eastern Federal University Votinova Olga

Yakutsk, Russia

Moscow Center of Fundamental and Applied Mathematics Shaporev Artemii

Moscow, Russia

Lomonosov Moscow State University Gulin Vyacheslav

Moscow, Russia

Systematic all-round examination of the viscoelastoplastic properties of nanocomposites with increased wear resistance based on polytetrafluoroethylene. Part 2 A description of the technology for manufacturing composites with increased wear resistance based on polytetrafluoroethylene (PTFE) is given. The composites were obtained by introducing mechanically activated layered silicates (kaolinite, serpentine, bentonite) and magnesium spinel as fillers. The main results of the study on wear resistance, structure and chemical composition of the friction surface using electronic microscopy and infrared spectroscopy and mechanical test data are presented, including families of tensile-to-failure curves at different strain rates, loading and unloading curves at different rates, and creep and recovery curves for different stress levels obtained in tests of pure PTFE and six PTFE composites particulate-filled with serpentine and magnesium spinel with a mass fraction ranging from 1 to 5 %. A primary analysis of materials loading history dependence was carried out, in particular: strain rate sensitivity, ability to flow under constant stress, deformability resource and ability to recover after unloading, and the influence of the composition, condition and proportion of fillers. The basic characteristics of materials have been determined: instantaneous modulus, yield strength, stress and strain at failure depending on the loading rate, etc. After examination using a scanning electron microscope, changes in the microstructure of PTFE and composites with different filler contents in the destruction zones of the samples were studied (compared to the original structure). When analyzing the accumulated volume of experimental data, high deformability of materials, pronounced loading history dependence, the ability of materials to creep (flow) under constant load and accumulate irreversible (plastic) strain, very high strain rate sensitivity, and a strong influence of small amounts of fillers on the structure and mechanical properties were discovered. Although the wear resistance of the studied composites is significantly higher than pure polytetrafluoroethylene (about 2000 times), their stress-strain curves are qualitatively little different from the PTFE curves: all curves have a long yield plateau and a hardening stage after it, stress increases with increasing tensile speed, and the tensile strength much less dependent on strain rate than the yield strength and strain at failure. An interesting physical effect is observed in load-unloading tests for sufficiently large given upper stress: a noticeable increase in strain continues at the initial stage of unloading and the maximum strain lags behind the loading peak. This "‎inertial" effect indicates a pronounced memory of the loading history and is observed both in pure PTFE and in all tested composites based on it. 10.18149/MPM.5342025_11 polytetrafluoroethylene nanocomposites wear resistance viscoelastoplastic properties stress-strain curves family strain rate sensitivity failure strains loading and unloading curves creep and recovery curves https://mpm.spbstu.ru/article/2025.109.11/ 11_khokhlov_et_al_(part_2).pdf