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Nano sandwich-like storage structure or device is commonly designed as diaphragm to extend nano-battery working life, or fabricated as nanocomposite anode materials to maximumly improve electrochemical performance in nano-battery systems. This work aims to investigate size-dependent dynamic mechanical-diffusion responses of multi-layered laminated sandwich-like nanocomposites subjected to shock loadings of molar concentration in the context of nonlocal diffusion-elasticity model by a semi-analytical technique via Laplace transformation. The results reveal that the diffusion isolation will be maximally improved and lager harmful chemical stresses can be reduced to some extent for proper materials nonlocal parameters and constants ratios of selected. [ABSTRACT FROM AUTHOR]

Porous materials have been widely used in aerospace, electronic communication, petrochemical and bio-medicine, etc. due to their attractive attributes such as low relative density, thermal and acoustical insulation and good permeability. For porous materials suffering high temperature gradient or ultrafast heating, etc., it is crucial to reveal the behaviors of the thermal-induced stress and deformation within them for guiding their potential applications and optimizations. In present work, the thermoelastic dynamic behaviors of a porous half-space subjected to a ramp-type heating is investigated based on the theory for thermoelastic porous materials and the three-phase-lag heat conduction model. The governing equations of the problem are formulated, and then, solved by using Laplace transform and its numerical inversion. The distributions of the nondimensional temperature, displacement, stress and volume fraction within the half-space are obtained and illustrated graphically. In calculation, the effects of time, ramp-heating time factor and thermal time-delay factors on the considered physical quantities are examined and discussed in detail. Comparisons of the variations of the considered quantities under three different theories are carried out and presented. [ABSTRACT FROM AUTHOR]

Viscoelastic laminated sandwich composite structure has been used as a new class of high-efficient structural damping in the passive vibration control systems. This work aims to investigate transient thermo-viscoelastic responses of viscoelastic laminated sandwich composite structure. The effects of fractional order parameters and material constants ratio on the structural transient thermo-viscoelastic responses are evaluated and discussed. For each homogeneous isotropic layer, the governing equations are formulated and solved by Laplace transformation techniques. The results are expected to provide new insights on the vibration control and thermal management of viscoelastic laminated sandwich composite structure under extreme non-isothermal conditions. [ABSTRACT FROM AUTHOR]

Based on the generalized thermoelasticity with memory-dependent derivative, the transient response of a half-space heated by a non-Gaussian laser beam on its boundary is investigated. The coupled governing equations containing thermal time-delay factor and thermal kernel function, which can be chosen to adapt to specific problems, are formulated and solved by the Laplace transform technique and its numerical inversion. For the functionally graded half-space, its material properties are assumed to exponentially vary with material coordinate. In calculation, the non-dimensional temperature, displacement as well as stress under different thermal time-delay factor, thermal kernel function and functionally graded parameter are obtained and illustrated graphically. The results show that: with the decrease of thermal time-delay factor or the increase of exponent n of thermal kernel function, the peak value of the non-dimensional temperature, displacement and the absolute value of peak value of stress increase; negative temperature value, positive displacement and stress values will appear when functionally graded parameter is less than zero. It is hoped that the obtained results would be helpful in designing the functionally graded materials heated by a non-Gaussian laser beam in engineering. [ABSTRACT FROM AUTHOR]

Viscoelastic nanomaterials (e.g., ethylene glycol-Al2O3, ethylene glycol-ZnO, etc.) have become one of the most promising candidates for nanodevices/nanocomposites, which are widely used as high-efficient nano colloidal dampers, nano-sensors, and nano-actuators in nanoengineering due to their excellent mechanical, thermal, and chemical properties. Present study aims to develop a complete size-dependent thermo-viscoelastic coupling model accounting for two fundamentally distinct size-dependent models which govern the nonlocal feature of heat transport and viscoelastic deformation, respectively. The proposed model is applied to investigate the transient responses of a bi-layered composite viscoelastic nanoplate with nonidealized interfacial conditions of thermal contact resistance and elastic wave impedance. [ABSTRACT FROM AUTHOR]

The instantaneous change of concentration in the rapid charging of Li-ions batteries can result in the Li-ions diffusion and diffusion-induced stresses. In such situation, the accurate description of the interaction mechanism between mass diffusion with matter is of great importance for the fabrication and exploitation of nano-electrochemical devices under non-uniform concentration in-service environment. To deal with such problems, this paper aims to establish a size-dependent diffusion-elasticity model is with the consideration of spatial nonlocal effects of concentration and strain fields. The proposed model is then applied to investigate the dynamic responses of a thick nanoplate under transient concentration loads. [ABSTRACT FROM AUTHOR]

In this work, we shall formulate the fibre-reinforced two-dimensional problem of thermoelasticity for an infinite space weakened by a finite linear opening mode-I crack. In the context of the fractional order theory of generalized thermoelasticity proposed by Sherief et al., we focus on investigating the dynamic response and the governing equations of the problem are formulated and solved by means of normal mode analysis. The distributions of the considered non-dimensional temperature, displacement and stress are obtained and illustrated graphically. The effects of fractional order parameter, rotation, crack dimension on the variations of the considered variables are investigated, and the results show that this parameter has significant influence on the variations of the considered variables. [ABSTRACT FROM AUTHOR]

AbstractThis work aims to study the nonlinear transient coupled thermo-electromechanical dynamic responses of the piezoelectric structure with the high-order temperature-dependent material properties. The multi-field coupling nonlinear model is established based on the non-Fourier thermoelasticity theories by introducing the function of high-order temperature dependency of the arbitrary material property. The virtual work principle and the nonlinear finite element approach are proposed to investigate the two-dimensional case of the orthotropic rectangular piezoelectric plate of the crystal class mm2 subjected to the zonal transient heating loads. The influences of the high-order temperature-dependent material parameters on the structural responses and wave propagations are discussed. [ABSTRACT FROM AUTHOR]

The dynamic response of a one-dimensional thermo-piezoelectric problem with variable material properties is investigated in the context of fractional order theory of thermoelasticity. The system of governing equations for the thermo-piezoelectric problem is formulated and then solved by means of Laplace transform together with its numerical inversion. The distributions of the considered non-dimensional displacement, temperature, and stress are obtained and illustrated graphically. The effects of fractional order parameter and temperature-dependent properties on the considered quantities are investigated and the results show that they have significant influence on the variations of the considered quantities. [ABSTRACT FROM AUTHOR]

The transient thermo-piezoelectric response of a functionally graded piezoelectric rod subjected to a moving heat source is investigated in the context of fractional order theory of thermoelasticity proposed by Sherief. The material properties of the functionally graded piezoelectric rod are assumed to vary exponentially along the length, except for the thermal relaxation time and the specific heat, which are taken to be constant. To solve the governing equations of the problem, Laplace transform is applied, eliminating the time effect; the analytical solutions of the displacement, stress, temperature, and electric field in Laplace domain are obtained. Subsequently, the solutions of the considered variables in time domain are obtained by numerical Laplace inversion and illustrated graphically. In calculation, the effect of the fractional order parameter on the variations of the considered variables is presented. [ABSTRACT FROM PUBLISHER]

The dynamic response of a piezoelectric-thermoelastic rod made of piezoelectric ceramics (PZT-4) subjected to a moving heat source is dealt with in the context of the fractional order theory of thermoelasticity. The piezoelectric-thermoelastic governing equations for the problem are formulated and then solved by means of Laplace transform together with its numerical inversion. The distributions of the considered nondimensional temperature, displacement, stress, and electric potential are obtained and illustrated graphically. The effects of fractional order parameter and the velocity of heat source on the variations of the considered variables are investigated, and the results show that they have significant influence on the variations of the considered variables. The present investigation could be helpful for better understanding the multi-field coupling effect of mechanical, electric, and thermal fields in real piezoelectric ceramics structures, and provide some guidelines in the optimal design of actuators or sensors made of piezoelectric ceramics serving in a thermoelastic environment. [ABSTRACT FROM PUBLISHER]

Abstract In recent years, the application of porous materials in practical engineering has become increasingly common. Under extreme thermal conditions, how to accurately describe the heat conduction and structural response of porous materials is a key issue in the structural safety and functional design of porous materials. Among them, it is particularly important to consider the size-dependent and memory-dependent effects for small-sized structures or microdevices of porous materials. To address these issues of porous structures and to guide their applications as well as optimization, this paper first investigates the thermoelastic transient response of porous microplates subjected to thermal and stress shocks at the left boundary based on the Atangana-Baleanu (AB) fractional-order generalized thermoelastic theory by considering nonlocal effects and fractional-order strain, which is combined with the thermoelasticity theory of porous materials and the dual-phase-lag (DPL) heat conduction model. The governing equations are then established and solved using the Laplace transform and its numerical inversion. Finally, the effects of newly defined fractional order parameters, nonlocal parameters and the initial magnitude of the mechanical shock on the dimensionless temperature, volume fraction field, displacement and stress distribution are discussed and displayed graphically. [ABSTRACT FROM AUTHOR]

AbstractThe extraordinary properties of graphene nanoplatelets (GPLs) have attracted great attention in the thermomechanical behaviors. Additionally, thermoelastic damping (TED), as a dominant intrinsic dissipation mechanism, is a major challenge in optimizing high-performance micro/nano-resonators. However, the classical TED models fail to explain the thermomechanical behavior considering the influences of the small-scale effect and the memory-dependent effect. To fill these gaps, the present study aims to investigate TED analysis of functionally graded (FG) microplate resonators reinforced with GPLs in the frame of the modified strain gradient theory and the fractional dual-phase-lag heat conduction model. Four patterns of GPLs distribution namely the UD, FG-O, FG-X, and FG-A pattern distributions are taken into account, and the effective material properties of the plate-type nanocomposite are evaluated based on the Halpin–Tsai model. The energy equation and the motion equation in the Kirchhoff microplate model are solved, and then, the closed-form analytical expression of TED is obtained by complex frequency technique. A detailed parametric study has been conducted to discuss the influence of the material length-scale parameter, the fractional-order parameter, and the total weight fraction of GPLs on the TED. The results demonstrated that the energy dissipation of FG microplate resonators reinforced with GPLs is determined by the small-scale effect, the memory-dependent effect, and the total weight fraction of GPLs. This article provides a theoretical approach to predict TED in the design of FG microplate resonators reinforced with GPLs with high performance. [ABSTRACT FROM AUTHOR]

AbstractThermo-electromechanical coupling analysis at micro and nano temporal and spatial scales becomes significantly important with extensive application of ultrafast heating technology to micro/nano-machining and manufacturing of piezoelectric micro/nano-devices, where the size effects in heat conduction and elastic deformation remarkably increase. This article aims to establish a new nonlocal piezoelectric thermoelasticity theory based on newly developed model of Eringen-type nonlocal single-phase-lag heat conduction via Eringen’s nonlocal continuum mechanics. The proposed model is applied to analyze the thermo-electromechanical responses of piezoelectric nanorod by Laplace transformation technique. The effects of nonlocal characteristic lengths on wave propagations and structural transient response are evaluated and discussed. [ABSTRACT FROM AUTHOR]