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AbstractMicro/nano-scale transient thermo-mechanical responses are significantly important with rapid development and applications of ultra-short pulse in micro-machining of viscoelastic structure. This work aims to establish non-Fourier thermo-viscoelastic model based on nonlocal single-phase-lag heat conduction and Eringen’s differential elasticity. The developed model is applied to study thermo-viscoelastic responses for 1D temperature-dependent polymer-based rods subjected to non-Gaussian laser pulse excitation by Kirchhoff and Laplace transformation techniques. The results reveal that the parameters of the deformation, pulse laser, and nonlocal single-phase-lag heat conduction remarkably affect the wave propagations and thermo-viscoelastic response at micro/nano-scale nanoscale. [ABSTRACT FROM AUTHOR]

In this work, high temperature and large temperature gradient are addressed for the first time in the topology optimization of thermo‐elastic structures. The conventional assumption of constant material properties (CMPs) is broken through with the full consideration of temperature‐dependent material properties (TDMPs) including thermal conductivity, elastic tensor, and coefficient of thermal expansion. Nonlinear heat conduction is thus implemented to give varying temperature fields in thermoelasticity. The maximum displacement of the specified region is taken as the objective function in the formulation of the optimization problem. The Kreisselmeier‐Steinhauser (KS) function is employed to approximate the regional maximum displacement/temperature. Corresponding sensitivity analyses, which are carried out using the adjoint method, theoretically reveal how TDMPs affect the thermo‐elastic optimization problem. Typical numerical examples are investigated to validate the proposed approach. The results show that the use of TDMPs produces optimized structures of high fidelity with displacements precisely predicted and temperature constraints rigorously satisfied under large temperature gradient, while thermo‐elastic analysis and optimization with CMPs lead to undesirable designs with significant inaccuracy. [ABSTRACT FROM AUTHOR]

The thermo-elastic response of plates functionally graded in two directions (2D-FGRPs) is investigated by the theory of elasticity. Material properties are a function of temperature and are graded along the plane. The finite difference method (FDM) is used to solve the transient heat conduction and the Elasticity's Navier equations. Sets of linear equations are solved by singular value decomposition (SVD). This study aims to determine the temperature dependence of the material properties of 2D-FGRPs and the effect of composition gradient on temperature and stress levels. It is emphasized that the material properties of 2D-FGRP change significantly with temperature. [ABSTRACT FROM AUTHOR]

• Plates with temperature-dependent material properties are studied. • A slice model is built for discretization. • An iteration algorithm is developed to obtain the temperature distribution. • The 3-D thermoelasticity theory is applied in the analysis. • Effects of surface temperature and layer thickness ratio on the plates are studied. The analytical solutions are presented for the distributions of temperature, displacements, and stresses in simply-supported layered rectangular plates under thermo-mechanical loads. The material properties of every layer are temperature-dependent. A slice model is presented for discretization: dividing every layer into finite thin slices, the material properties within each slice are assumed to be uniform. The temperature varies along the thickness and follows the one-dimensional (1-D) heat conduction equations. An iterative algorithm is proposed for the prediction of the 1-D temperature field. Then, the exact three-dimensional (3-D) thermoelasticity theory and the transfer matrix technique are applied for the prediction of the displacement and stress fields in the plate. The influences of temperature can be divided into two parts: producing thermal deformations and thermal stresses and affecting the deformations and stresses induced by mechanical loads. Finally, the influences of the surface temperature and the layer thickness ratio on the thermo-mechanical responses of a sandwich plate are studied in detail. Image, graphical abstract [ABSTRACT FROM AUTHOR]

This study focuses on the thermoelastic behavior of simply supported thick beams with temperature-dependent material properties under thermomechanical loads. The heat conduction analysis is based on the one-dimensional Fourier's law, and the displacement and stress analysis is based on the two-dimensional thermoelasticity theory. The solution of temperature field across the thickness is obtained. By dividing the beam into a series of thin slices, the temperature and the material properties in each slice are considered to be uniform. The state space method is used to give the displacements and stresses for every slice. The transfer-matrix method is used to give the displacements and stresses for the beam. Finally, an example is conducted to analyze the temperature, displacement, and stress fields in a carbon steel beam. The example reveals that the temperature not only produces displacements and stresses itself but also affects the displacements and stresses induced by the mechanical load. [ABSTRACT FROM AUTHOR]

In this paper, a nonlinear static thermoelastic analysis of a spherical shell made of functionally graded material is performed. The material properties are assumed to be functions of both radial coordinate of the sphere and temperature. The dependence on temperature makes the governing equations nonlinear. The so-obtained nonlinear heat conduction equation is analytically solved using the perturbation technique. The approximate temperature field is then supplied to elasticity equations which are solved exactly for the case of incompressible elastic material to get displacement and stress distributions. Finally, the temperature field, material properties and radial stress versus the radial direction are shown and discussed. [ABSTRACT FROM AUTHOR]

A nonlinear thermoelastic analysis of a thick-walled cylinder made of functionally graded material is performed. The dependence of material properties on temperature is taken into account. This makes the governing equations nonlinear. Thus, the perturbation technique is employed to solve the nonlinear heat conduction equation analytically. The so-obtained temperature field is then supplied to elasticity equations which are solved exactly for the case of incompressible elastic material to get displacement and stress distributions. Finally, the temperature field, material properties and radial stress versus the radial direction are plotted and discussed. [ABSTRACT FROM AUTHOR]

In this paper, a non-Fourier heat conduction model of ultra-short pulsed laser ablation of metal is established that takes into account the effect of the heat source, laser heating of the target, the evaporation and phase explosion of target material, the formation and expansion of the plasma plume, and interaction of the plasma plume with the incoming laser. Temperature dependent optical and thermophysical properties are also considered in the model due to the properties of the target will change over a wide range during the ultra-short pulsed laser ablation process. The results show that the plasma shielding has a great influence on the process of ultra-short pulsed laser ablation, especially at higher laser fluence. The non-Fourier effect has a great influence on the temperature characteristics and ablation depth of the target. The ultra-short pulsed laser ablation can effectively reduce the heat affected zone compared to nanosecond pulsed laser ablation. The comparison between the simulation results and the experimental results in the literature shows that the model with the plasma shielding and the non-Fourier effect can simulate the ultra-short pulsed laser ablation process better. [ABSTRACT FROM AUTHOR]