Materials physics and mechanics

RAR RUS 237-242 0000-0003-1619-309X Peter the Great St. Petersburg Polytechnic University Rybin

St.Petersburg, Russia

0000-0002-0437-8540 Mechanical Engineering Research Institute, Russian Academy of Science Perevezentsev

Nizhni Novgorod, Russia

Mechanical Engineering Research Institute, Russian Academy of Science Svirina

Nizhni Novgorod, Russia

Investigation of the influence of strain induced junction disclinations on hardening and nucleation of cracks during plastic deformation of polycrystals An influence of elastic field of strain induced junction disclinations on hardening and nucleation of a micro-crack in a head of edge lattice dislocations pile-up is considered. Computer simulation method is used to calculate critical external stress for plastic shear propagation throw a force barrier induced by junction disclination. A qualitative explanation is given for the experimentally observed essential growth of the flow stress at sufficiently large plastic deformations. It is shown that the appearance of junction disclinations suppress nucleation of micro-cracks according to the mechanism of pile-up head dislocations confluence proposed by Stroh [1]. 10.18720/MPM.3232017_1 strain induced junction disclination plastic deformation hardening crack nucleation https://mpm.spbstu.ru/article/2017.56.1/ MPM332_01_rybin.pdf

RAR RUS 243-252 IBM Research, Zurich Research Laboratory Müller

Rüschlikon, Switzerland

Institute for Problems in Mechanical Engineering of the Russian Academy of Sciences Vilchevskaya

St.Petersburg, Russia

Micropolar media with structural transformations . theory illustated by an example problem This paper is concerned with a model for an extended theory of micropolar media. The extension concerns the balance for the tensor field of the moment of inertia, which in contrast to previous theories contains a production term. This term becomes important if the micropolar material undergoes structural changes. In the present case we consider an assemblage of hollow spheres, which due to a transient temperature field contract or expand. This leads to a true field for the tensor of the moment of inertia varying in space and time. For this situation the production term can be calculated numerically. In addition, the temporal and spatial change of the macroscopic inertia field influences rotational motion. Based on a numerical solution for the balance of spin we study the evolvement of angular velocity in space and time. The importance of the presence of a volume couple density is stressed and its physical realization will be discussed. 10.18720/MPM.3232017_2 micropolar media production of microinertia balances of angular momentum and spin volume couple https://mpm.spbstu.ru/article/2017.56.2/ MPM332_02_muller.pdf

RAR RUS 253-257 Saint Petersburg State University E.G. Zemtsova

St.Petersburg, Russia

7005573911 St.Petersburg State University Morozov N.F.

St.Petersburg, Russia

Institute for Problems of Mechanical Engineering of the RAS Semenov

St.Petersburg, Russia

Ufa State Aviation Technical University Valiev R.Z.

Ufa, Russia

Saint Petersburg State University Smirnov

St.Petersburg, Russia

Mechanical properties of nanostructured titanium with bioactive titanium-organic nanocoating We present here the results of the study of mechanical properties of the nanostructured titanium samples fabricated by means of the severe plastic deformation that has titanium organic brush-like nanostructures on the surface. Based on the mechanical properties of the samples, we established for the first time that the gas-phase ALD synthesis at 200-400 °C of titanium organic nanocoatings with height of 220 nm and the distances between nanostructures up to 200 nm does not lead to deterioration of the mechanical properties of the nanostructured titanium. 10.18720/MPM.3232017_3 nanostructured titanium; equal channel angular pressing; brush-like nanostructure; titanium organic nanocoating; mechanical properties https://mpm.spbstu.ru/article/2017.56.3/ MPM332_03_zemtsova.pdf

RAR RUS 258-261 Saint Petersburg State University Evstifeev

St.Petersburg, Russia

St.-Petersburg State University Chevrychkina

St.Petersburg, Russia

St.-Petersburg State University Petrov

St.Petersburg, Russia

Dynamic strength properties of an ultra-fine-grained aluminum alloy under tension conditions Experimental and theoretical analysis of aluminum alloy 1230, subjected to static and dynamic tension is presented in the paper. The material was tested in two conditions - initial coarse-grained (CG) state and ultrafine-grained (UFG) state. Experimental results were processed using incubation time fracture criterion. 10.18720/MPM.3232017_4 dynamic impact fracture nanostructured material strength criterion https://mpm.spbstu.ru/article/2017.56.4/ MPM332_04_evstifeev.pdf

RAR RUS 262-271 St. Petersburg Academic University RAS Koryakin

St.Petersburg, Russia

P-4505-2016 7006034020 0000-0002-2973-8645 Institute of Problems of Mechanical Engineering RAS Kukushkin S.A. sergey,a.kukushkin@gmail.com

St.Petersburg, Russia

Institute of Problems of Mechanical Engineering of Russian Academy of Sciences Redkov

St.Petersburg, Russia

Nucleation and growth mechanisms of CdTe thin films on silicon substrates with silicon carbide buffer layers The kinetics of the initial growth stages of cadmium telluride (CdTe) films on silicon substrates covered with silicon carbide (SiC) buffer layers grown by the method of topochemical substitution of atoms is investigated theoretically. The model based on the classical nucleation theory is proposed to depict the CdTe film growth by the method of thermal evaporation and condensation in vacuum. The model accounts for the mechanical stresses caused by the lattice mismatch and difference of thermal expansion coefficients of CdTe film and substrate. The influence of substrate and evaporator temperature on the nucleation mechanism and kinetics of the initial growth stages of CdTe film is estimated. The different growth regimes of CdTe films on the SiC/Si substrates are discussed, and the optimal growth conditions are found. It is shown that the elastic stresses in the CdTe/SiC/Si structure are approximately three times lower than the elastic stresses in the CdTe film grown coherently on the Si substrate without the SiC buffer layer. This leads to the large difference in the nucleation rates of the CdTe films on the SiC/Si substrate and Si substrate. The diagram of the nucleation rates of CdTe islands on the SiC/Si depending on the substrate and evaporator temperature is presented. 10.18720/MPM.3232017_5 thin film; CdTe; SiC; Si; silicon substrate; silicon carbide buffer layer; growth; nucleation; thermal evaporation https://mpm.spbstu.ru/article/2017.56.5/ MPM332_05_koryakin.pdf

RAR RUS 272-277 Peter the Great St. Petersburg Polytechnic University Linkov

St.Petersburg, Russia

On influence of shear traction on hydraulic fracture propagation The paper concerns with the problem important for proper simulation of hydraulic fractures. Its objective is to answer the recently raised question: Can we neglect the impact of the hydraulically induced shear stress when using the elasticity equation, which connects the fracture opening with the net-pressure? The estimations, given in the paper, show that the answer is “Yes”. The impact can be confidently neglected. Its influence is well beyond physical significance, computational abilities of computers and practical applications of HF. 10.18720/MPM.3232017_6 hydraulic fracture shear traction elasticity equation https://mpm.spbstu.ru/article/2017.56.6/ MPM332_06_linkov.pdf

RAR RUS 278-287 Institute for Problems in Mechanical Engineering of Russian Academy of Science Shubin

St.Petersburg, Russia

Norwegian University of Science and Technology Akulichev

Trondheim, Norway

Institute of Problems of Mechanical Engineering RAS Freidin A.B.

St.Petersburg, Russia

Elastomer composites based on filler with negative coefficient of thermal expansion: experiments and numerical simulations of stress-strain behaviour We consider composites made of hydrogenated nitrile butadiene rubber (HNBR) and particles of zirconium tungstate (ZrW2O8). We focus on finite element (FE) modelling of a finite-strain mechanical behaviour of the composite and validation of the numerical simulation against experiments. Based on examination of composite microstructure by scanning electron microscope and optical analysis of particle images, realistic representative volume elements (RVE) of microstructure are generated taking into consideration the particles circularity and size distributions. Then FE simulations are performed to study the influence of the microstructure and matrix-filler interface conditions on the mechanical properties of the composites. It is assumed that the mechanical behaviour of rubber is non-linear, while the tungstate particles are modelled by a linear elastic material. The FE simulations reproduce uniaxial compression tests. Two types of interface condition between matrix and particles are simulated: a perfect adhesion and absence of adhesion. Corresponding stress-strain curves are constructed. Comparison with experiments shows that the real stress-strain curves for preloaded samples path within intervals given by the modelling, i.e. pre-loading leads to partial damage of bonding between matrix and particles. 10.18720/MPM.3232017_7 elastomer composite representative volume element effective stress-strain curve damage debonding https://mpm.spbstu.ru/article/2017.56.7/ MPM332_07_shubin.pdf

RAR RUS 288-292 ITMO University Shirshneva-Vaschenko

St.Petersburg, Russia

ITMO University Sokura

St.Petersburg, Russia

ITMO University Liashenko

St.Petersburg, Russia

ITMO University Podlesnov

St.Petersburg, Russia

ITMO University V.E. Bougrov

St.Petersburg, Russia

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

St.Petersburg, Russia

Fabrication of p-type transparent oxide films with delafossite structure by sol-gel processing CuAlO2, CuAl1-хMgхO2, CuCrO2, CuCr1-хMgхO2 and CuAl0.5Cr0.5O2 thin films were deposited on quartz substrates by sol-gel processing using spin coating technique. The elemental compositions, synthesis mechanisms, optical transmittance and resistivity of prepared films were studied. CuAl0.5Cr0.5O2 films had the best characteristics under lower temperature of synthesis. Optical transmittance of CuAl0.5Cr0.5O2 reached 70 % in visible region. The resistivity of CuAl0.5Cr0.5O2 was 0,4 kΩ·cm and was stable with time. Thus, CuAl0.5Cr0.5O2 films may have potential applications for transparent optoelectronics as pconductivity transparent oxides. 10.18720/MPM.3232017_8 p-type transparent oxide films; quartz substrate; delafossite structure; sol-gel processing https://mpm.spbstu.ru/article/2017.56.8/ MPM332_08_shirshneva.pdf

RAR RUS 298-304 Ufa State Aviation Technical University Valiev R.Z.

Ufa, Russia

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

Moscow, Russia

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

Moscow, Russia

Application of quantum-chemical modeling results in experimental investigations of silicone composites The results of direct numerical simulation obtained earlier, within the clusterquantum-chemical approximation, are used in experimental investigations of polydimethylsiloxane composites with shungit. The surface structure of these composites by scanning electron and atomic force microscopy was studied. Correlation of the distribution of micro and nano - dimensional filler in the polymer matrix with the physical mechanical properties of the elastomers was established. 10.18720/MPM.3232017_9 polydimethylsiloxane composites nanoshungit filler scanning electron and atomic force microscopy https://mpm.spbstu.ru/article/2017.56.9/ MPM332_09_valiev.pdf

RAR RUS 298-304 Tver State University Zubchaninov

Tver, Russia

Tver State University Alekseev

Tver, Russia

Tver State University Alekseeva

Tver, Russia

Tver State Technical University Gultiaev

Tver, Russia

Experimental verification of postulate of isotropy and mathematical modeling of elastoplastic deformation processes following the complex angled nonanalytic trajectories The results of numerical simulation for 45 steel deformation with the use of general and linearized models of the theory of processes along flat smooth trajectories with curvilinear sectors are presented. The results of calculation are compared with the data of thin-walled cylindrical specimen deformation experiment, carried out on SN-EVM testing complex. It is shown that for the realized types of experimental trajectories symmetric with respect to the bisector of a right angle Ilyushin.s postulate of isotropy is fulfilled in the proper way. 10.18720/MPM.3232017_10 elastoplastic deformation; postulate of isotropy; numerical simulation https://mpm.spbstu.ru/article/2017.56.10/ MPM332_10_zubchaninov.pdf

RAR RUS 298-304 Tver State University Zubchaninov

Tver, Russia

Tver State Technical University Gultiaev

Tver, Russia

Tver State University Alekseev

Tver, Russia

Tver State Technical University Garanikov

Tver, Russia

Tver State Technical University Subbotin

Tver, Russia

Testing of steel 45 under complex loading along the cylindrical screw trajectories of deformation The results of the experiment on complex loading of a thin-walled tubular steel specimen with three parameter action of axial force, torsion, and internal pressure are presented. The experiment was carried out on A.A. Ilyushin's testing complex SN-EVM. The program of the experiment in the deformation space is a cylindrical, helical trajectory with a displaced center of a screw curvature. Scalar and vector properties of the material steel 45 were investigated. 10.18720/MPM.3232017_11 plasticity; complex loading; trajectory of deformation; helical trajectory; scalar and vector properties of material; thin-walled tubular steel https://mpm.spbstu.ru/article/2017.56.11/ MPM332_11_zubchaninov.pdf

RAR RUS 312-320 Peter the Great St. Petersburg Polytechnic University Borovkov A.I.

St.Petersburg, Russia

Peter the Great St. Petersburg Polytechnic University Klyavin

St.Petersburg, Russia

Peter the Great St. Petersburg Polytechnic University Rozhdestvenskiy

St.Petersburg, Russia

Peter the Great St. Petersburg Polytechnic University Aleshin

St.Petersburg, Russia

peter Leontev Peter the Great St. Petersburg Polytechnic University Nikulina

St.Petersburg, Russia

Peter the Great St. Petersburg Polytechnic University Okunev

St.Petersburg, Russia

Validation of the mathematical model of isotropic material using parametric optimization of its physical and mechanical characteristics In the article the questions connected with modeling of isotropic material on an example of carbon steel St3ps [1] for subsequent use in analysis of power protective frames of cabins of agricultural machinery in accordance with regulatory requirements are considered [14]. The choice of the Johnson-Cook (JC) material model for performing tasks of this type is substantiated. Full-scale tests of steel specimens were carried out, on the basis of which the mathematical model of material was validated. 10.18720/MPM.3232017_12 isotropic material; carbon steel; Johnson-Cook material model https://mpm.spbstu.ru/article/2017.56.12/ MPM332_12_borovkov.pdf

RAR RUS 321-327 Peter the Great St. Petersburg Polytechnic University Tsaplin

St.Petersburg, Russia

Peter the Great St. Petersburg Polytechnic University Kuzkin

St.Petersburg, Russia

On using quasi-random lattices for simulation of isotropic materials Elastic properties of three-dimensional lattices are usually anisotropic. This fact limits the range of applicability of lattice models in solid mechanics problems. In the present paper, we propose a simple three-dimensional lattice model with isotropic elastic properties. A quasi-random lattice is generated by randomly displacing particles of the face-centered cubic lattice. Then particles are connected by linear and angular springs such that initially forces in all springs are equal to zero. It is shown numerically that the resulting quasi-random lattice has isotropic elastic properties, provided that amplitudes of random displacements are sufficiently large. Poisson’s ratio of the lattice depends on number of angular springs per particle and stiffnesses of these springs. In the present model, values of Poisson’s ratio belong to the interval [0;0.41]. The model can be used, in particular, for simulation of deformation and brittle fracture of rocks in hydraulic fracturing. 10.18720/MPM.3232017_13 particle dynamics; quasi-random lattice; face-centered cubic lattice; effective elastic properties; isotropy; molecular dynamics https://mpm.spbstu.ru/article/2017.56.13/ MPM332_13_tsaplin.pdf

RAR RUS 328-352 Peter the Great St. Petersburg Polytechnic University Shymchenko

St.Petersburg, Russia

Peter the Great St. Petersburg Polytechnic University Tereshchenko

St.Petersburg, Russia

Peter the Great St. Petersburg Polytechnic University Ryabov

St.Petersburg, Russia

Peter the Great St. Petersburg Polytechnic University Salkutsan

St.Petersburg, Russia

Peter the Great St. Petersburg Polytechnic University Borovkov A.I.

St.Petersburg, Russia

Review of the computational approaches to advanced materials simulation in accordance with modern advanced manufacturing trends In order to be competitive, modern manufacturers have to offer best-in-class products. Superior quality of the product requires introduction of new materials, digital design methods and advanced manufacturing technologies into production process. Special attention is given to numerical simulation as the most time efficient, flexible and cheap method to evaluate the level of optimality and viability of the proposed solution as well as to predict further Product Life-Cycle. Accurate setting of material properties and representation of complex material structure is crucial for product design employing simulation. Commonly, material representation for simulation purpose is based on the analytical relationships that provide approximate data and cannot provide multiscale information about structure. Initiation of Material Genome Initiative (MGI) as well as the study of Big Data and Machine Learning concepts leads to development of new, more accurate and reliable instruments for product design that involve material simulation and optimization of material selection process. 10.18720/MPM.3232017_14 Factory of Future (FoF) Material Genome Initiative (MGI) Integrated Computational Materials Engineering (ICME) Computer-Aided Engineering Big-Data Machine Learning https://mpm.spbstu.ru/article/2017.56.14/ MPM332_14_shymchenko.pdf

RAR RUS 353-369 Institute of the Applied Mechanics Russian Academy of Science Lurie

Moscow, Russia

Institute of the Applied Mechanics Russian Academy of Science Belov

Moscow, Russia

Institute of the Applied Mechanics Russian Academy of Science Solyaev

Moscow, Russia

Aristotle University of Thessaloniki Aifantis E.C.

Thessaloniki, Greece

On one class of applied gradient models with simplified boundary problems We consider the generic gradient elasticity theory of Mindlin-Tupin and try to establish a class of applied models of gradient elasticity, for which the boundary value problems of the gradient theory with static boundary conditions are divided into a sequence of two subtasks, one of which is classical. Such applied models are very effective in applications, because their solutions reduce exactly to a consistent solution of boundary value problems of the second and not of the fourth order. We consider gradient theories with a general structure of tensors of gradient modules that satisfy potentiality conditions and additional symmetry conditions, which is considered as a criterion of correctness. It is shown that their gradient tensors of the elastic modules are represented in the form of an expansion with respect to the tensor basis of five sixth-rank tensors, three of which satisfy a special property. Each of these basis tensors is represented as a convolution of fourth-rank tensors, and the corresponding quadratic form is a convolution of vectors. It is shown that for the traditional gradient Mindlin-Tupin theory, the “classical” static conditions on the body surface are not satisfied locally. However, if the gradient modules are represented as a convolution of the “classical” tensors of elastic moduli, then the set of the boundary value problems of such gradient theory admits a full fractionation of the initial boundary value problem into two: the “classical” boundary value problem and the “cohesive” boundary value problem. It is established the structure of the applied gradient models with such property of separating boundary value problems. They are particular cases of gradient elasticity theories with gradient modulus tensors, representable in the form of an expansion in three basis tensors of the sixth rank, satisfying the properties of the representation in the form of convolution via fourth-rank tensors.We formulated “vector” gradient Mindlin-Tupin model that preserves the classical form of static boundary conditions. Such a model leads to a specific variant of the gradient theory with a single non-classical modulus, or one-parametrical model. It is shown that the obtained gradient model can be considered as some generalization of the well-known applied theoryGradEla providing for it the separation of boundary value problems. 10.18720/MPM.3232017_15 gradient theories scale parameters separation of boundary value problems "classical" displacement field "cohesive" displacement field https://mpm.spbstu.ru/article/2017.56.15/ MPM332_15_lurie.pdf

RAR RUS 370-382 Peter the Great St. Petersburg Polytechnic University Churilova

St.Petersburg, Russia

Peter the Great St. Petersburg Polytechnic University Frolov

St.Petersburg, Russia

Comparison of adaptive algorithms for solving plane problems of classical and cosserat elasticity Paper continues developments and numerical testing of functional approach [1-3] to a posteriori error control for 2D problems of classical [2] and Cosserat elasticity [4,5]. The approach yields reliable error bounds (majorants) that are valid for all conforming solutions of problems regardless of methods used for a numerical implementation of a solution process. Efficiency of the above technique is shown on a set of numerical examples including consequent mesh adaptations with MATLAB tools as it was done [6]. 10.18720/MPM.3232017_16 computational mechanics; a posteriori error estimates; finite element method https://mpm.spbstu.ru/article/2017.56.16/ MPM332_16_churilova.pdf

RAR RUS 383-392 Peter the Great St. Petersburg Polytechnic University Stepanov

St.Petersburg, Russia

Peter the Great St. Petersburg Polytechnic University Loboda

St.Petersburg, Russia

«CADFEM-CIS» Novozhilov

St.Petersburg, Russia

Boston Children’s Hospital, Harvard Medical School Vasilyev

Boston, Massachusetts, USA

Finite element modelling of the mitral valve repair using an implantable leaflet plication clip We report the results of numerical simulation of the mitral valve in human heart. The beam-shell geometry model was created based on anatomical atlases and taking into account the heterogeneity of distribution of the mitral valve's leaflets thickness. The full cycle of the mitral valve opening and closure was simulated using the finite element analysis software ANSYS Mechanical. The method of data processing from a computer tomography in a solid CAD model was implemented and tested. 10.18720/MPM.3232017_17 mitral valve finite element simulation computed tomography https://mpm.spbstu.ru/article/2017.56.17/ MPM332_17_stepanov.pdf