Materials physics and mechanics

RAR RUS 99-111 Institute of Problems of Mechanical Engineering RAS Meshcheryakov Yu.I.

St.Petersburg, Russia

Institute of Problems of Mechanical Engineering RAS Divakov

St.Petersburg, Russia

Institute of Problems of Mechanical Engineering RAS Zhigacheva

St.Petersburg, Russia

Institute for Problems of Mechanical Engineering of the RAS Konovalov

St.Petersburg, Russia

The CRISM “Prometey” Barakhtin

St.Petersburg, Russia

Central Research Institute for Constructional Materials “Prometei” Kalinin

St.Petersburg, Russia

Central Research Institute for Constructional Materials “Prometei” Fomina

St.Petersburg, Russia

Dynamic strength of nitrogen steels Three kinds of nitrogen steel of different structural state are tested under uniaxial shock conditions. The first kind of steel (A1) contains a maximum density of second phase particles - carbonitrides, nitrides and delta-ferrite. To provide stability of austenite structure, interval of allying in chrome, manganese, nitrogen and nickel for A2 and A3 steels has been narrowed. The dynamic strength characteristics of steels are shown to depend on the shock- induced structural transition. The highest dynamic strength is found for A3 steel where the structural transition has not been initiated. nitrogen steel; dynamic strength; structural transition https://mpm.spbstu.ru/article/2014.36.1/ MPM221_01_zigacheva.pdf

RAR RUS 112-118 Ioffe Institute Mynbaev

St.Petersburg, Russia

Ioffe Institute Shilyaev

St.Petersburg, Russia

Ioffe Institute Bazhenov

St.Petersburg, Russia

R&D Institute for Materials SRC “Carat” Izhnin

Lviv, Ukraine

R&D Institute for Materials SRC “Carat” Izhnin

Lviv, Ukraine

Tomsk State University Voitsekhovskii

Tomsk, Russia

A.V. Rzhanov Institute of Semiconductor Physics, Siberian Branch of RAS Mikhailov

Novosibirsk, Russia

A.V. Rzhanov Institute of Semiconductor Physics, Siberian Branch of RAS Varavin

Novosibirsk, Russia

A.V. Rzhanov Institute of Semiconductor Physics, Siberian Branch of RAS Dvoretsky

Novosibirsk, Russia

Light emission from CdHgTe-based nanostructures Optically excited light emission from CdHgTe nanostructures with 12 to 1100 nm- wide potential wells was studied. The structures were grown by molecular beam epitaxy on GaAs substrates. For structures with size quantization, radiative transitions between the levels of the electrons and light holes were observed. For structures with broad potential wells, optical transitions related to exciton localized at potential fluctuations were recorded. In the latter case, the significant degree of the alloy disorder led to the broadening of photoluminescence (PL) spectra and a considerable Stokes shift that could be traced up to temperature T~230 K. Annealing of the structures improved the ordering and led to the increase in the PL intensity. A remarkable feature of the PL of the structures was rather small decrease of its intensity with temperature increasing from 84 to 300 K. This effect was explained by localization of carriers at potential fluctuations. CdHgTe nanostructures; light emission https://mpm.spbstu.ru/article/2014.36.2/ MPM221_02_mynbaev.pdf

RAR RUS 119-125 Togliatti State University Gryzunova

Togliatti, Russia

Togliatti State University Vikarchuk

Togliatti, Russia

Togliatti State University M.R. Shafeev

Togliatti, Russia

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

St.Petersburg, Russia

Morphological and phase transformations in nickel coatings on stainless steel in temperature fields The work is devoted to the development of nickel containing all metal catalysts with high surface area. We show that the use of certain technological methods allows fabricating large surface area metal net carriers and nickel containing coatings with special phase compositions including iron, chromium and nickel oxides. nickel coatings; stainless steel; morphological transformations; phase transformations https://mpm.spbstu.ru/article/2014.36.3/ MPM221_03_gryzunova.pdf

RAR RUS 126-134 59122315900 0000-0002-1572-2108 Kurukshetra University Kumar Rajneesh

Kurukshetra, India

Govt. Degree College Chowari (Chamba) Kumar

India

Himachal Pradesh University Gourla

India

Interaction due to expanding surface loads in thermoporoelastic medium The present investigation is concerned with interaction due to expanding surface loads in thermoporoelastic medium whose surface is subject to loads that suddenly emanate from a point on the surface and expand radially at constant rate. The cases of loads shaped as a ring and disc are considered in detail to show the utility of the approach. These loads are chosen so that they exert a constant force on the surface as they expand. Laplace and Hankel transform technique is used to solve the problem. The expressions for displacement components, stress components, pore pressure and temperature change are obtained in the transformed domain. To obtain the resulting quantities in the physical domain, a numerical inversion technique is applied. Effect of porosity is shown on the resulting quantities. A particular case of interest is also deduced from the present investigation. thermoporoelastic medium; expanding surface loads https://mpm.spbstu.ru/article/2014.36.4/ MPM221_04_kumar.pdf

RAR RUS 135-142 RTM Nagpur University Deshmukh

Maharashtra, India

Kamala Nehru Mahavidyalaya Khandait

Maharashtra, India

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

Kurukshetra, India

Thermal stresses in a simply supported plate with thermal bending moments with heat sources In this paper, we consider a thin simply supported rectangular plate defined as 0 ≤ x ≤ a, 0 ≤ y ≤ b, 0 ≤ z ≤ c and determined the temperature distribution function with heat generation. The thermal stress components σxx, σyy, σxy are evaluated due to thermal bending moments. The results are obtained in the series forms in terms of trigonometric function. Also two special cases for point heat source and moving heat source are considered. thermoelastic problem; thermal stresses; heat generation https://mpm.spbstu.ru/article/2014.36.5/ MPM221_05_deshmukh.pdf

RAR RUS 147-167 59122315900 0000-0002-1572-2108 Kurukshetra University Kumar Rajneesh

Kurukshetra, India

Kurukshetra University Ahuja

India

Deenbandhu Chhotu Ram University Garg

Murthal (Sonipat), India

Reflection and transmission of plane waves at the loosely bonded interface of an elastic solid half-space and a microstretch thermoelastic diffusion solid half-space The problem of reflection and refraction phenomenon due to plane waves incident obliquely at the loosely bonded interface between an elastic solid half-space and the microstretch thermoelastic diffusion solid half-space is discussed. It is assumed that the interface behaves like a dislocation, which preserves the continuity of traction while allowing a finite amount of slip. The amplitude ratios of various reflected and transmitted waves to that of incident wave are obtained. These amplitude ratios are further used to find the expressions of energy ratios of various reflected and refracted waves to that of incident wave. Numerical results have been obtained for a particular model to study the variation of energy ratios with respect to angle of incidence. The effect of relaxation times and loosely bonding parameters are shown with energy ratios for a specific model. The law of conservation of energy at the loosely boundary interface is verified. Some special cases of interest have been deduced from the present investigation. microstretch; thermoelastic diffusion solid; bonding parameter; plane waves; energy ratios https://mpm.spbstu.ru/article/2014.36.6/ MPM221_06_kumar.pdf

RAR RUS 168-176 Dalian University of Technology Jin

Dalian, China

Dalian University of Technology Fei

Dalian, China

Dalian University of Technology Liqi

Dalian, China

Ping-pong fixed abrasive diamond wire saw slicing piezoelectric crystal quartz Fixed abrasive diamond wire saw is widely used for slicing crystal quartz to manufacture new piezoelectric dynamometers. However, the process has always the problem of slicing out-of-straight influencing the dynamometer.s indicators, the optimization methods of machining and slicing process are studied in the paper. Developments of fixed abrasive diamond wire machining are reviewed firstly. A research system is built to monitor process and measure cutting forces. The 3-axis forces and their relationship with tension-force are investigated by measured curve. Force analysis of diamond wire at changing direction is shown in the experiment and the rule of slicing straight is found. Finally, suggestions on slicing parameters and methods are put forward. ping-pong diamond wire saw; process monitoring; crystal quartz https://mpm.spbstu.ru/article/2014.36.7/ MPM221_07_jin.pdf

RAR RUS 177-193 Karunya University Selvamani

India

Dynamic response of a heat conducting solid bar of polygonal cross sections subjected to moving heat source The dynamic response of a heat conducting solid bar of polygonal cross section subjected to moving heat source is discussed using the Fourier expansion collocation method (FECM). The equations of motion are formulated using the three dimensional constitutive equation of elasticity and generalized thermo elastic equation composed of linear homogeneous isotropic material. Three displacement potential functions are introduced to uncouple the equations of motion and the heat conduction. The frequency equations are obtained by satisfying the boundary conditions along the surface of the polygonal solid bar using Fourier expansion collocation method. The numerical calculations are carried out for triangular, square, pentagonal and hexagonal cross sectional bars with different moving heat source speeds. Dispersion curves are plotted for longitudinal and flexural (antisymmetric) modes of non dimensional frequency. polygonal cross sections of a solid bar; elastic bars with fluid; wave propagation in bar; moving heat source; dynamics in plates and panels vibration of arbitrary cross sectional plates vibration of thermoelastic bar https://mpm.spbstu.ru/article/2014.36.8/ MPM221_08_selvamani.pdf

RAR RUS 194-199 Ioffe Institute Maslov

St.Petersburg, Russia

Ioffe Institute Krymov

St.Petersburg, Russia

Ioffe Institute Kalashnikov

St.Petersburg, Russia

Ioffe Institute Nikolaev

St.Petersburg, Russia

Single crystals of β-Ga2O3, grown from the melt of gallium and aluminum oxides Tabular β-Ga2O3 single crystals were grown by method of free crystallization from Ga2O3-Al2O3 melt. Growth mechanisms and properties of the crystals have been studied; main features of optical behavior and defect structure of the crystals have been revealed. tabular β-Ga2O3 single crystals; crystal growth; optical behavior; defect structure https://mpm.spbstu.ru/article/2014.36.9/ MPM221_09_maslov.pdf

RAR RUS 200-205 Ioffe Institute Shpeizman

St.Petersburg, Russia

Ioffe Institute Orlova T.S.

St.Petersburg, Russia

Ioffe Institute Smirnov B.I.

St.Petersburg, Russia

Universidad de Sevilla Gutierrez-Pardo

Sevilla, Spain

Universidad de Sevilla Ramirez-Rico

Sevilla, Spain

Influence of catalytic graphitization on mechanical properties of carbonized biocarbon The uniaxial compression strength and the deformation characteristics of beech-derived biocarbon, partially graphitized by the use of Ni-catalyst in the process of carbonization at different temperatures, have been measured using high-precision interferometry. It has been shown that the room temperature strength and the value of inelastic strain at the fracture point are very low for the carbonization temperature range of 1200-1500 °С. The curves of deformation consist of small jumps corresponding to displacements of 4-7 and 100-150 nm at the nanometer level, as well as to displacements of 1-3 µm at the micrometer level. The influence of the catalyst on the values of nanometer jumps and the number of micrometer ones have been observed. The results obtained are compared with previously published measurements of the elastic properties and the internal friction of this material and with the strength and strain characteristics of the beech-derived biocarbon carbonized without a catalyst. biomorphic carbon; catalytic graphitization; strength; microplastic strain https://mpm.spbstu.ru/article/2014.36.10/ MPM221_10_shpeizman.pdf