Materials physics and mechanics

RAR RUS 1-6 University of Southern California Kassner

Los Angeles, USA

Recent developments in understanding the creep of aluminum This paper summarizes the recent creep research by the author on pure aluminum including classic five power-law creep, Harper-Dorn creep, ambient-temperature creep and an investigations of long-range internal stresses in creep-deformed aluminum. Many of the models and theories for these phenomena persisted for a relatively long period of time. More recent developments in these phenomena are discussed that may lead to new interpretations of creep in aluminum, as well as creep in other crystalline materials. 10.18720/MPM.4012018_1 creep Harper-Dorn five-power law creep dislocation hardening long-range internal stress low-temperature creep https://mpm.spbstu.ru/article/2018.65.1/ MPM140_01_kassner.pdf

RAR RUS 7-11 ITMO Univesity V.G. Dubrovskii

St.Petersburg, Russia

A simplified model explaining the formation of InAs nanowires on GaAs nanomembranes Gold-free GaAs nanomembranes have proven ideal templates for further growth of in-plane III-V nanowires. Recently, it has been demonstrated that high quality InAs nanowires with a low defect density can be obtained on top of GaAs nanomembranes by molecular beam epitaxy in wafer-scale approach and provide an excellent platform for future investigations into one-dimensional transport and quantum computation. Here, we develop a model to explain why InAs NWs form spontaneously on the top ridges of GaAs nanomembranes and not elsewhere. We speculate that the driving force for this growth mechanism is the free energy minimization including the elastic and surface energy contributions. 10.18720/MPM.4012018_2 InAs nanowires GaAs nanomembranes elastic stress relaxation growth model https://mpm.spbstu.ru/article/2018.65.2/ MPM140_02_dubrovskii.pdf

RAR RUS 12-21 Southern Federal University Nasedkin

Rostov-on-Don, Russia

Southern Federal University Nasedkina

Rostov-on-Don, Russia

Southern Federal University Rybyanets

Rostov-on-Don, Russia

Numerical analysis of effective properties of heterogeneously polarized porous piezoceramic materials with local alloying pore surfaces The paper considers homogenization problems for porous piezoceramic material with partially metallized pore surfaces. It is assumed that the thickness of the metal layer at the boundaries of the pores is infinitesimally small, and the metallization effect is entirely described by setting the boundary conditions for equipotential surfaces. Following previous research of the authors, here the heterogeneity of piezoceramic polarization was taken into account. The homogenization problems were solved, using the effective moduli method, the finite element method, and the representative volumes with random closed porosity. An analysis of the effective moduli on porosity was carried out for homogeneous and inhomogeneous polarization fields. 10.18720/MPM.4012018_3 piezoelectricity porous piezoceramics microstructure metallized micropores nonuniform polarization effective moduli representative volume finite element method https://mpm.spbstu.ru/article/2018.65.3/ MPM140_03_nasedkin.pdf

RAR RUS 22-36 Beirut Arab University Gazo Hanna

Beirut, Lebanon

Ecole Centrale de Nantes Poitou

Nantes, France

University of Nantes Casari

Saint Nazaire, France

Modeling the interply slip during forming of thermoplastic laminates Interply slip plays an important role in composite forming processes, the resulting product geometry, final fiber orientations and fiber stresses. This interply slip will depend on fiber/resin properties, the fibers distribution, the reinforcement architecture and the process conditions. In this paper, a new model, based on Reynolds equation for thin film lubrication, was developed to predict the frictional behavior of these materials. This approach should be validated by means of experiments. 10.18720/MPM.4012018_4 thermoforming interply slip thermoplastic wrinkles https://mpm.spbstu.ru/article/2018.65.4/ MPM140_04_gazo-hanna.pdf

RAR RUS 37-46 Peter the Great St. Petersburg Polytechnic University Antonov

St.Petersburg, Russia

Porubov porubov@math.ioffe.ru Peter the Great St. Petersburg Polytechnic University Bessonov

St.Petersburg, Russia

Two-dimensional model for hydraulic fracturing with foams The effect of non-homogeneity in a magneto electro elastic plate of polygonal cross sections is studied using the linear theory of elasticity. The wave equation of motion based on two-dimensional theory of elasticity is applied under the plane strain assumption of plate of polygonal shape, composed of non-homogeneous transversely isotropic material. The frequency equations are obtained by satisfying the irregular boundary conditions of the polygonal plate using Fourier expansion collocation method. The analytical results obtained in the physical domain have been computed numerically for Triangle, Square, Pentagon and Hexagonal plates. The results for stress, strain, displacements, induced electric and magnetic fields have been presented graphically. 10.18720/MPM.4012018_5 magneto-electro elastic cylinder solid with polygonal cross sections Fourier expansion collocation method stresses/vibration transducers sensors/actuators MEMS/NEMS https://mpm.spbstu.ru/article/2018.65.5/ MPM140_05_antonov.pdf

RAR RUS 47-55 Institute of Problems of Mechanical Engineering RAS Nazarov

St.Petersburg, Russia

"Wandering" natural frequencies of an elastic cuspidal plate with the clamped peak Cuspidal irregularities of solids have been recognized as Vibrating Black Holes for elastic and acoustic waves. The corresponding absorption phenomenon is caused, in particular, by the appearance of the continuous spectrum [k† , +∞) of the Lame system in a two-dimensional plate with the sharp cusp that provokes for wave processes in a finite volume. However, if the plate is clamped in the small h-neighborhood of the cusp top, the spectrum becomes discrete and consists of isolated natural frequencies kjh of finite multiplicity. The asymptotics of kjh as h → +0 is constructed that describes the effect of the "wandering" of the natural frequencies above the threshold k† > 0, namely the asymptotic formula kjh = Kj (ln h) + O (hδ) with δ > 0 is valid where Kj is a periodic function. In other words, some of frequencies flounce in the semi-axis (k† , +∞) at a quite high rate O (h-1). At the same time, natural frequencies below the threshold get the sustainable behaviour kph = kp0 + O (hδ), δ > 0, as h → +0. 10.18720/MPM.4012018_6 vibrating black holes cuspidal plate continuous spectrum clamped peak wandering eigenvalues asymptotics https://mpm.spbstu.ru/article/2018.65.6/ MPM140_06_nazarov.pdf

RAR RUS 56-62 Institute of Continuous Media Mechanics UB RAS Garishin

Perm, Russia

Institute of Continuous Media Mechanics UB RAS Shadrin

Perm, Russia

Institute of Continuous Media Mechanics UB RAS Belyaev

Perm, Russia

Foundation Russian Academy of Sciences, Institute of Applied Mechanics RAS Kornev

Moscow, Russia

Micro and nanoshungites - perspective mineral fillers for rubber composites used in the tires Physical-mechanical properties of rubber filled by mineral filler (micro and nanoparticles of shungite) were studied experimentally. To date, shungite is one of the most promising materials used in the tire industry as active reinforcing fillers. Experiments on uniaxial tensile at break showed that input of this filler leads to a significant increase in rubber strength. Investigation of thermo-viscoelastic properties of these materials using dynamo-mechanical analyzer (DMA) were also carried out. As a result, the dynamic and viscous modulus dependences on the frequency (at 20°C) and their temperature dependences (from -50 to +100°C) were constructed. 10.18720/MPM.4012018_7 rubber composite shungite filler strength dynamo-mechanical analyzer https://mpm.spbstu.ru/article/2018.65.7/ MPM140_07_garishin.pdf

RAR RUS 63-70 Karunya Institute of Technology and Sciences Selvaraj

India

Optimization of surface roughness of duplex stainless steel in dry turning operation using Taguchi technique This paper presents the results of experimental work carried out in dry turning operation of nitrogen alloyed duplex stainless steel ASTM A 995 Grade 5A. In this investigation, the cutting parameters considered were cutting speed, feed rate and depth of cut. The effects of these cutting parameters on the surface roughness were analyzed using Taguchi technique. The results revealed that the feed rate is the most important parameter affecting the surface roughness, followed by cutting speed and depth of cut. The minimum surface roughness was obtained when the process parameters were set at their optimum values. 10.18720/MPM.4012018_8 duplex stainless steel dry turning surface roughness Taguchi technique https://mpm.spbstu.ru/article/2018.65.8/ MPM140_08_selvaraj.pdf

RAR RUS 71-77 Ioffe Institute Krasinkova

St.Petersburg, Russia

Fullerene molecule as a nanosize quantum system It is shown that a strong Coulomb and exchange interactions between π electrons in a fullerene molecule lead to the localization of these electrons, quantization of their energies, and a highly correlated state manifesting itself in the formation of electron crystals. In this approximation the fullerene molecule is a nanosize quantum system consisting of a positively charged rolled-up carbon backbone surrounded by three electron crystals: (i) two crystals formed by π electrons in the 2 pz state that participate in the π bond formation through the resonance of structures and are located on the convex and concave sides of the molecule, and (ii) the crystal formed by pairs of π* electrons excited into the 2pz 3s state and participating in the formation of nonresonant π* bonds. The chemical activity and physical properties of such a system are determined by the crystal formed by electron pairs. 10.18720/MPM.4012018_9 fullerenes highly correlated electron state electron crystals nanosize quantum system https://mpm.spbstu.ru/article/2018.65.9/ MPM140_09_krasinkova.pdf

RAR RUS 78-83 ITMO University Shirshnev

St.Petersburg, Russia

ITMO University Snezhnaia

St.Petersburg, Russia

ITMO University Shirshneva-Vaschenko

St.Petersburg, Russia

F-1445-2014 7202768874 0000-0003-3738-408X ITMO University Romanov Alexey alexey.romanov@niuitmo.ru

St.Petersburg, Russia

ITMO University V.E. Bougrov

St.Petersburg, Russia

Relation of the optical properties of boron copper-containing glasses on the concentration of lithium In this work, optical properties of a variety of boron host glasses with copper in relation to the lithium content from 0 to 25 % are studied. It is shown that with the increase of the lithium concentration the absorption band of Cu2+ increases. This fact is associated with the interaction of lithium ions in the melt with atmospheric oxygen. It is shown that the photoluminescence band shifts by more than 20 nm upon excitation at 320 nm with increasing lithium concentration. This is can be explained by the high splitting of the levels of Сu(I) under the action of lithium ions, and also with the formation of Cu+ -Cu+ dimers in the glass structure. 10.18720/MPM.4012018_10 boron copper-containing glasses lithium content optical properties https://mpm.spbstu.ru/article/2018.65.10/ MPM140_10_shirshnev.pdf

RAR RUS 84-103 Karunya University Selvamani

India

Sri Krishna College of Technology Sujitha

Tamil Nadu, India

Effect of non-homogeneity in a magneto electro elastic plate of polygonal cross-sections The effect of non-homogeneity in a magneto electro elastic plate of polygonal cross sections is studied using the linear theory of elasticity. The wave equation of motion based on two-dimensional theory of elasticity is applied under the plane strain assumption of plate of polygonal shape, composed of non-homogeneous transversely isotropic material. The frequency equations are obtained by satisfying the irregular boundary conditions of the polygonal plate using Fourier expansion collocation method. The analytical results obtained in the physical domain have been computed numerically for Triangle, Square, Pentagon and Hexagonal plates. The results for stress, strain, displacements, induced electric and magnetic fields have been presented graphically. 10.18720/MPM.4012018_11 magneto-electro elastic cylinder solid with polygonal cross sections Fourier expansion collocation method stresses/vibration transducers sensors/actuators MEMS/NEMS https://mpm.spbstu.ru/article/2018.65.11/ MPM140_11_selvamani.pdf

RAR RUS 104-111 The Shukshin Altai State Humanities Pedagogical University Eremin

Biysk, Russia

Altai State Humanitarian and Pedagogical University. V.M. Shukshin Zakharov

Biysk, Russia

I.I. Polzunov Altai State Technical University Starostenkov

Barnaul, Russia

Statistical characteristics of a quasi-breather with a hard type of nonlinearity in a CuAu crystal By the method of molecular dynamics a study in the work is made of the statistical characteristics of a quasi-breather in a model CuAu crystal. The phonon spectrum of this model crystal, the dependences of mean-square deviation, the coefficient of variation and the average frequency of the model quasi-breather on the time of its existence are obtained. The statistical data analysis allows for the conclusion that the quasi-breather model solution in the model considered (which uses the interatomic potential obtained by means of embedded atom method (EAM)) slightly differs from the one in the corresponding exact breather. 10.18720/MPM.4012018_12 quasi-breather discrete breather nonlinear dynamics soliton https://mpm.spbstu.ru/article/2018.65.12/ MPM140_12_eremin.pdf

RAR RUS 112-116 Islamic Azad University Fazeli Kisomi

Iran

Islamic Azad University Mousavi

Iran

Ab initio calculations of structural and thermal properties of wurtzite Zn1-xCdxO alloys with Debye-Gruneisen model In this paper, structural and thermal properties of Zn1-xCdxO alloys for x=0, 0.125, 0.25, 0.375, 0.5, and 0.625 have been investigated by Ab initio calculations method. Both lattice constants a and c of wurtzite structure follow Vegard's law and are in a good agreement with the experimental data for x=0. The diagrams of specific heat at constant volume versus temperature for different values of x have been plotted and values of specific heat at constant pressure for different concentrations of x at 300K, 600K and 900K have been obtained. The value of specific heat at constant pressure for ZnO has a good consistency with experimental data. Specific heat at constant volume increased by increasing temperature and specific heat at constant pressure decreased by increasing x. The diagrams of Debye temperature versus x at 0K, 300K, 600K and 900K have been plotted, too. These diagrams state that Debye temperature decreases by increasing x or increasing temperature. 10.18720/MPM.4012018_13 ab initio calculations thermal properties Debye-Gruneisen model Zn1-xCdxO alloy. https://mpm.spbstu.ru/article/2018.65.13/ MPM140_13_kisomi.pdf

RAR RUS 117-123 Peter the Great St. Petersburg Polytechnic University Magazinov

St.Petersburg, Russia

Peter the Great St. Petersburg Polytechnic University Krivosheev

St.Petersburg, Russia

Peter the Great St. Petersburg Polytechnic University Adamyan

St.Petersburg, Russia

Peter the Great St. Petersburg Polytechnic University Alekseev

St.Petersburg, Russia

Peter the Great St. Petersburg Polytechnic University Titkov

St.Petersburg, Russia

Peter the Great St. Petersburg Polytechnic University Chernenkaya

St.Petersburg, Russia

Adaptation of the magnetic pulse method for conductive materials testing The paper presents the results of experimental testing by magnetic-pulse method of Cu-ETP samples with crack type macro defect. Three-dimensional modeling of the magnetic field in the loading device -sample system was performed, on the basis of which the magnetic pressure was calculated and mechanical simulation was performed with Johnson-Cook plasticity model and fracture criteria. Comparison of the obtained results of residual deformation indicates the applicability of Johnson Cook plasticity model for OFHC copper for describing the behavior of Copper ETP in the deformation rate range up to 104 1/s. 10.18720/MPM.4012018_14 high speed deformation magnetic-pulse loading Johnson-Cook plasticity model https://mpm.spbstu.ru/article/2018.65.14/ MPM140_14_magazinov.pdf

RAR RUS 124-132 Irkutsk National Research Technical University Zenkov

Irkutsk, Russia

Irkutsk State University of Railway Transport Tsvik

Irkutsk, Russia

Increasing the reliability the combined criteria of the static strength of a material of complexly loaded deformable structures The article deals with the relevance of the stress strain state (SSS) in areas of potential destruction for the assessment of deformed structures strength. The article develops a calculation and experimental method for building a combined strength criterion equation involving strength coefficients, introduced by Pisarenko-Lebedev criterion equation with regard to the real SSS type. The proposed method has been implementedand experimental mechanical tests were carried out for the selected samples which follow the idea that the SSS type in the active zone is identical to the SSS of the analyzed structure in the area of interest. Results of the calculations and experimental tests demonstrate a significant decrease in the limit strength value for 50CrV (high quality) under biaxial tension in comparison with the conventional limit strength value. 10.18720/MPM.4012018_15 modeling stress strain state limit state equation prismatic sample finite element method strength parameters biaxial stretching https://mpm.spbstu.ru/article/2018.65.15/ MPM140_15_zenkov.pdf