• Earthquakes and Structures
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• v.10 no.3
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• pp.681-697
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• 2016

The model of two-temperature magneto-thermoelasticity for a non-simple variable-thermal-conductivity infinitely-long solid cylinder is established. The present cylinder is made of an isotropic homogeneous thermoelastic material and its bounding plane is traction-free and subjected to a time-dependent temperature. An exact solution is firstly obtained in Laplace transform space to obtain the displacement, incremental temperature, and thermal stresses. The inversion of Laplace transforms has been carried out numerically since the response is of more interest in the transient state. A detailed analysis of the effects of phase-lags, an angular frequency of thermal vibration and the variability of thermal conductivity parameter on the field quantities is presented.

• Proceedings of the Korean Magnestics Society Conference
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• 2008.12a
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• pp.158.2-158.2
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• 2008

• Coupled systems mechanics
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• v.10 no.1
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• pp.39-60
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• 2021

The present paper is concerned with the study of nonlinear ultrasonic waves in a magneto thermo (MT) elastic armchair single-walled carbon nanotube (ASWCNT) resting on polymer matrix. The analytical formulation is developed based on Eringen's nonlocal elasticity theory to account small scale effect. After developing the formal solution of the mathematical model consisting of partial differential equations, the frequency equations have been analyzed numerically by using the nonlinear foundations supported by Winkler-Pasternak model. The solution is obtained by ultrasonic wave dispersion relations. Parametric work is carried out to scrutinize the influence of the non local scaling, magneto-mechanical loadings, foundation parameters, various boundary condition and length on the dimensionless frequency of nanotube. It is noticed that the boundary conditions, nonlocal parameter, and tube geometrical parameters have significant effects on dimensionless frequency of nano tubes. The results presented in this study can provide mechanism for the study and design of the nano devices like component of nano oscillators, micro wave absorbing, nano-electron technology and nano-electro- magneto-mechanical systems (NEMMS) that make use of the wave propagation properties of armchair single-walled carbon nanotubes embedded on polymer matrix.

• Fire Science and Engineering
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• v.16 no.2
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• pp.8-13
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• 2002

Induction heating is widely used in today's industry, in operations such as metal hardening, pre-heating for forging operations, melting or cooking. In this paper, the magneto-thermal analysis of an induction heating jar(IH-JAR) was presented as an efficient design. The magnetic field intensity inside the axisymmetric shaped cooker was analyzed using three-dimensional axisymmetric finite element method(FLUX2D) and the effectual heat source was obtained by ohmic losses from eddy currents induced in the jar. The heat was calculated using the heat source and heating equation. Also, it was presented the temperature characteristics of the IH-JAR according to time and relative permeability in stainless parts and in aluminum parts.

• Journal of the Korean Vacuum Society
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• v.12 no.S1
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• pp.7-9
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• 2003

Solid-state reactions in Ni/Si multilayered films (MLF) with an overall stoichiometry of $Ni_2Si$, NiSi and $NiSi_2$, induced by ion-beam mixing (IBM) and thermal annealing, were studied by using spectroscopic ellipsometry and magneto-optical spectroscopy as well as x-ray diffraction (XRD). The mixing was performed with Ar+ ions of an energy of 80 keV and a dose of $1.5 x\times10^{16}$ $Ar^+$/$\textrm{cm}^2$. It was shown that the IBM induces structural changes in the Ni/Si MLF, which cannot be detected by XRD but are confidently recognized by the optical method. A thermal annealing at 673 K of the Ni/Si MLF with an overall stoichiometry of NiSi and $NiSi_2$ causes formation of the first η -NiSi phase. The first trace for $NiSi_2$ phase on the background of NiSi one was detected by XRD after an annealing at 1073 K while, according to the optical results, $NiSi_2$ turns out be the dominant phase for the annealed Ni/Si MLF with an overall stoichiometry of $NiSi_2$.

• Earthquakes and Structures
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• v.9 no.3
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• pp.577-601
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• 2015

The thermomagnetic effect on plane wave propagation at the liquid-solid interface with nonclassical thermoelasticity is investigated. It is assumed that liquid-solid half-space is under initial stress. Numerical computations are performed for the developed amplitude ratios of P, SV and thermal waves under Cattaneo-Lord-Shulman theory, Green-Lindsay theory and classical thermoelasticity. The system of developed equations is solved by the application of the MATLAB software at different angles of incidence for Green and Lindsay model. The effect of initial stress and magnetic field in the lower half-space are discussed and comparison is made in LS, GL and CT models of thermoelasticity. In the absence of magnetic field, the obtained results are in agreement with the same results obtained by the relevant authors. This study would be useful for magneto-thermoelastic acoustic device field.

• Journal of Magnetics
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• v.8 no.4
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• pp.133-137
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• 2003

The magnetostatic properties of the as-deposited and annealed at T=300 and 400$^{\circ}C$ Ni films were investigated employing both magneto-optical magnetometer and VSM. The Ni films of 50∼200 nm thicknesses were prepared by DC magnetron sputtering technique. The strong influence of annealing temperature on magnetostatic properties of the studied samples was discovered. For the annealed Ni films, the increase of the coercivity H$_c$ (up to 4 times) in comparison with that of as-deposited samples was revealed. The obtained results were explained by using crystallographic structural data of the samples.

• Advances in materials Research
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• v.9 no.4
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• pp.289-309
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• 2020

The aim of the present investigation is to examine the propagation of plane harmonic waves in transversely isotropic homogeneous magneto visco thermoelastic rotating medium with fractional order heat transfer and two temperature. It is found that, for two dimensional assumed model, there exist three types of coupled longitudinal waves (quasi-longitudinal, quasi-transverse and quasi-thermal) in frequency domain. phase velocities, specific loss, penetration depth, attenuation coefficients of various reflected waves are computed and depicted graphically. The effects of viscosity and fractional order parameter by varying different values are represented graphically.

• Coupled systems mechanics
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• v.10 no.2
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• pp.103-121
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• 2021

The present research deals with the investigation of the effect of hall current in an orthotropic magneto-thermoelastic medium with two temperature in the context of multi-phase-lag heat transfer due to thermomechanical sources. The bounding surface is subjected to linearly distributed and concentrated loads(mechanical and thermal source).Laplace and Fourier transform techniques are used to solve the problem. The expressions for displacement components,stress components and conductive temperature are derived in transformed domain and furtherin physical domain with the help of numerical inversion techniques. The effect ofrotation and hall parameter hasshown with the help of graphs.

• Structural Engineering and Mechanics
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• v.77 no.3
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• pp.315-327
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• 2021

Here, in this research we have studied a two dimensional problem in a homogeneous orthotropic magneto-thermoelastic medium with higher order dual-phase-lag heat transfer with combined effects of rotation and hall current in generalized thermoelasticity due to time harmonic sources. As an application the bounding surface is subjected to uniformly distributed and concentrated loads (mechanical and thermal source). Fourier transform technique is used to solve the problem. The expressions for displacement components, stress components and temperature change are derived in frequency domain. Numerical inversion technique has been used to obtain the results in physical domain. The effect of frequency has been depicted with the help of graphs.