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Plane, nonlinear Rayleigh wave propagation is investigated in a three-layer sandwich structure of a thermoelastic medium, within the frame of dual-phase-lag theory. The thermal conductivity is taken as a linear function of temperature. This induces nonlinearity in the evolution equations for the heat flux components. A particular solution is found in the form of Poincaré expansion in a small parameter that reflects the fluctuations of temperature about a steady value. This solution is discussed and plots are provided for a special case when both external faces of the structure are traction-free and under prescribed temperature regime. It is noted, in particular, that some quantities of practical interest suffer jumps at the interfaces. Some of the jumps appear only starting from the second order of approximation. The existence of jumps may be favourably used to carry out some measurements of material parameters. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study is to investigate the bending analysis of metal (Ti-6Al-4V)-ceramic (ZrO2) functionally graded material (FGM) sandwich plate with material property gradation along length and thickness direction under thermo-mechanical loading using inverse trigonometric shear deformation theory (ITSDT). FGM sandwich plate with a ceramic core and continuous variation of material properties has been modelled using Voigt's micro-mechanical model following the power law distribution method. The impact of bi-directional gradation of material properties over the bending response of FGM plate under thermo-mechanical loading has been investigated in this work. Design/methodology/approach: In this study, gradation of material properties for FGM plates is considered along length and thickness directions using Voigt's micromechanical model following the power law distribution method. This type of FGM is called bi-directional FGMs (BDFGM). Mechanical and thermal properties of BDFGM sandwich plates are considered temperature-dependent in the present study. ITSDT is a non-polynomial shear deformation theory which requires a smaller number of field variables for modelling of displacement function in comparison to poly-nominal shear deformation theories which lead to a reduction in the complexity of the problem. In the present study, ITSDT has been utilized to obtain the governing equations for thermo-mechanical bending of simply supported uni-directional FGM (UDFGM) and BDFGM sandwich plates. Analytical solution for bending analysis of rectangular UDFGM and BDFGM sandwich plates has been carried out using Hamilton's principle. Findings: The bending response of the BDFGM sandwich plate under thermo-mechanical loading has been analysed and discussed. The present study shows that centre deflection, normal stress and shear stress are significantly influenced by temperature-dependent material properties, bi-directional gradation exponents along length and thickness directions, geometrical parameters, sandwich plate layer thickness, etc. The present investigation also reveals that bi-directional FGM sandwich plates can be designed to obtain thermo-mechanical bending response with an appropriate selection of gradation exponents along length and thickness direction. Non-dimensional centre deflection of BDFGM sandwich plates decreases with increasing gradation exponents in length and thickness directions. However, the non-dimensional centre deflection of BDFGM sandwich plates increases with increasing temperature differences. Originality/value: For the first time, the FGM sandwich plate with the bi-directional gradation of material properties has been considered to investigate the bending response under thermo-mechanical loading. In the literature, various polynomial shear deformation theories like first-order shear deformation theory (FSDT), third-order shear deformation theory (TSDT) and higher-order shear deformation theory (HSDT) have been utilized to obtain the governing equation for bending response under thermo-mechanical loading; however, non-polynomial shear deformation theory like ITSDT has been used for the first time to obtain the governing equation to investigate the bending response of BDFGM. The impact of bi-directional gradation and temperature-dependent material properties over centre deflection, normal stress and shear stress has been analysed and discussed. [ABSTRACT FROM AUTHOR]

This paper explores the distribution and features of residual stresses formed by super duplex stainless steel pipe welding. Experimental investigations, which encompass an elevated temperature tensile test and metallographic observation along with a hardness test and residual stress measurement, were first conducted to obtain the mechanical properties at high base metal temperatures and to confirm whether or not the duplex stainless steel undergoes martensitic phase development during the welding process. Finally, experiments were performed to scrutinize the residual stress evolution through the metallurgical phase transformation in the weld region and its vicinity. A sequentially coupled 3D thermal, mechanical and metallurgical finite element (FE) model capable of incorporating the experimental consequences was established next. A 3D FE simulation of the girth welding process was conducted, and the axial and hoop residual stress profiles along the girth were evaluated. The results substantiate that martensitic phase evolution occurs in the process of cooling during the welding of super duplex stainless steel, and they also highlight the significance of taking the metallurgical phase transformation into account in the numerical reproduction of the girth welding process for the accurate expression of weld-induced residual stresses, which is especially important for precisely predicting hoop residual stresses. [ABSTRACT FROM AUTHOR]

Thermoelectric generator (TEG) with improved performance is a promising technology in power supply and energy harvesting. Existing studies primarily adopt constant material properties to investigate TEG performance. However, thermoelectric (TE) material properties are subjected to considerable variations with temperature. Thus, reasonable doubts have risen concerning the influence level of temperature-dependent material properties on TEG performance. To solve this problem, an efficient and a comprehensive one-dimensional numerical model is developed to fully consider the third-order polynomial temperature-dependent thermal conductivity, Seebeck coefficient, and electrical resistivity. Control volume and finite difference algorithms are compared, and experiments are conducted to verify the developed numerical model. The temperature distribution along the TE leg obviously differs from the parabolic shape, which is a classic temperature distribution under the assumption of constant material properties. Insights find that the local change rate of thermal conductivity and Thomson effect are the essential reasons for the abovementioned phenomenon. It has been found that Thomson heat is released in the part of the leg near the cold-end, whereas it is absorbed in the remaining parts of the leg near the hot-end. The electric power on the basis of constant material properties is confirmed to be accurate enough by the developed numerical model, but the parabolic shape of the TE efficiency can be only obtained when temperature-dependent material properties are considered. Furthermore, it is wise to improve the TE efficiency by structural optimization. The present work provides an efficient and a comprehensive one-dimensional numerical model to include temperature-dependent material properties. New insights into the temperature and heat flux distribution, Thomson influence, and structural optimization potential are also presented for the in-depth understanding of the TE conversion process. [ABSTRACT FROM AUTHOR]

A thermoelastic topology optimization is proposed for structures with temperature-dependent material properties. Different from the common assumption of constant material properties in traditional thermoelastic topology optimization, the temperature-dependent material properties related to mechanical and thermal fields are taken into account. The non-uniform temperature distribution of the structure is a design dependent field that may vary during the optimization, and the nonlinear heat transfer analysis is considered according to the large temperature gradient. Based on these, a thermoelastic topology optimization model considering temperature-dependent material properties is formulated. The sensitivities with respect to the design variables are derived and the Method of Moving Asymptotes (MMA) algorithm is used to update the topological design variables. A cooperation platform based on MATLAB and ABAQUS is developed for the proposed thermoelastic topology optimization method to deal with problems with arbitrary domains for the design of complex engineering structures. Several typical numerical examples are given to illustrate the effectiveness of the proposed method and show the important influence of the temperature-dependent material properties. [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]

This paper aims to investigate the influence of material uncertainties on the postbuckling behaviour of functionally graded porous beams reinforced with graphene platelets when subjected to a thermal environment. A comprehensive deterministic, as well as stochastic study, has been done by employing the stochastic finite element methodology. The temperature-dependent (TD) and temperature-independent (TID) material properties have been considered. The homogenized effective material properties such as Young’s modulus are estimated by using the Halpin-Tsai micromechanics model and the density, and thermal expansion coefficient by Voigt’s rule of mixture. The homogenized material properties are assumed to be varying along the thickness direction in a functionally graded manner. The developed formulation is based on higher-order shear deformation theory in conjunction with Von-Kármán type geometric non-linearity for the postbuckling analysis. A C0 finite element model is developed to solve the system of non-linear governing equations, which are solved numerically using the direct iterative procedure. The convergence and validation study of the developed formulation has also been performed with an independent Monte Carlo simulation to ensure the accuracy of the formulation. The influence of material uncertainty on the thermo-mechanical postbuckling behavior of FG-GPLRC porous beams has been discussed for low variability (randomness) in material design parameters such as porosity content, amount of nanofillers, and material properties (i.e., Young’s modulus, density of metal matrix, and nanofillers) respectively. It was revealed that uncertainties in material properties can significantly affect the postbuckling response of FG-GPLRC porous beams. [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]

This is a study on the development of a novel multi-material topology optimization scheme considering temperature-dependent thermoelastic properties for engineering structure design. Two cases, a three-point-bending beam under a uniform temperature field and a cantilever beam under a non-uniform temperature field, are investigated for the effects of thermoelastic properties on topology optimization. The proposed optimization scheme is compared with two existing topology optimization approaches: conventional topology optimization and thermoelastic topology optimization. The results show that the temperature-dependent elastic modulus dominantly influences the design optimization outcomes, in terms of material distribution, structural shape and compliance, while the temperature-dependent thermal expansion coefficient has a much more crucial impact on determining the material distribution and structural geometry than on compliance. Taken together, the findings demonstrate that the developed topology optimization scheme can be used to design thermally sensitive multi-materials in industrial applications, e.g. aerospace structures under high temperature and polymers in additive manufacturing. [ABSTRACT FROM AUTHOR]

This paper presents a nonlinear thermo-elastoplastic bending analysis of temperature-dependent functionally graded (FG) plates exposed to a combination of mechanical and thermal loads using an efficient three-dimensional (3D) truly meshless approach based on the local radial point interpolation method (LRPIM). In this model, while using a new radial basis function (RBF), it is well shown that the quality of the LRPIM shape functions is not affected by the shape parameter. The modified rule of mixtures is employed to locally evaluate the effective temperature-dependent parameters of the functionally graded material. To describe the plastic behavior of the FG plate, the von Mises yield criterion, isotropic strain hardening, and the Prandtl-Reuss flow rule are adapted. To demonstrate the high capability and efficiency of the present method, the current results are compared with other existing numerical and analytical results, which shows an excellent agreement. The effect of significant parameters such as material gradient, ceramic volume fraction, plate thickness-to-length ratio, and boundary conditions on the nonlinear bending response of FG plates has also been investigated. [ABSTRACT FROM AUTHOR]

In this study, nonlinear transient thermo-elastic analysis for a thick hollow 1D-FGM (functionally graded material) axisymmetric cylinder with finite length is investigated using higher-order graded finite element method. The material property gradations are along the radial direction and the power-law volume fraction and simple rule of mixture scheme are utilized to perform the effective material properties. As the cylinder exposed to high temperature, the temperature dependency of material properties is considered. So it led to nonlinear thermal conduction equation and in spite of the material distribution along one-direction by changing the temperature, the material properties are varied along two-direction with time. The nonlinear heat equation leads to 2D-temperature distribution for an axisymmetric cylinder. Also the thermal stress field would be different from an infinite cylinder which has been studied before. The temperatures, displacements and stresses for different values of volume fraction exponents along radial direction are investigated. It is revealed that the stresses and temperature in FGM cylinder are lower than the ceramic rich one. In other words, functionally graded cylinder wall gives better results in both stress and temperature cases than non-FGM cylinder. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study is to investigate Thermo-mechanical limit elastic speed analysis of functionally graded (FG) rotating disks with the temperature-dependent material properties. Three different material models i.e. power law, sigmoid law and exponential law, along with varying disk profiles, namely, uniform thickness, tapered and exponential disk was considered. Design/methodology/approach: The methodology adopted was variational principle wherein the solution was obtained by Galerkin's error minimization principle. The Young's modulus, coefficient of thermal expansion and yield stress variation were considered temperature-dependent. Findings: The study shows a substantial increase in limit speed as disk profiles change from uniform thickness to exponentially varying thickness. At any radius in a disk, the difference in von Mises stress and yield strength shows the remaining stress-bearing capacity of material at that location. Practical implications: Rotating disks are irreplaceable components in machinery and are used widely from power transmission assemblies (for example, gas turbine disks in an aircraft) to energy storage devices. During operations, these structures are mainly subjected to a combination of mechanical and thermal loadings. Originality/value: The findings of the present study illustrate the best material models and their grading index, desired for the fabrication of uniform, as well as varying FG disks. Finite element analysis has been performed to validate the present study and good agreement between both the methods is seen. [ABSTRACT FROM AUTHOR]

In this study, the thermal buckling and postbuckling of functionally graded (FG) nanocomposite annular sector plates reinforced by carbon nanotubes (CNTs) are numerically analyzed. The effective material properties of FG nanocomposite are temperature-dependent (TD) and evaluated via the modified micromechanical method and rule of mixture. Based on the higher-order shear deformation theory (HSDT) and using the principle of virtual work and variational differential quadrature (VDQ) approach, the unified weak form of discretized nonlinear governing equilibrium equations is derived. Then, by using the linear part of equations and solving the derived eigenvalue problem, the critical temperature rise and associated mode shapes are obtained, which are used as the initial guess in solving the nonlinear thermal postbuckling problem. The pseudo-arc-length method and an iterative solver are employed to obtain the nonlinear thermal postbuckling equilibrium path of the FG nanocomposite annular sector plates. The influences of geometrical parameters, boundary conditions (BCs), CNT volume fraction, and CNT distribution pattern on the critical temperature rise and thermal postbuckling behavior of the FG nanocomposite annular sector plates are evaluated and discussed. Also, comparisons are made between the results considering the TD and temperature-independent (TID) properties. It is demonstrated that for higher values of sector angle, the effect of sector angle on the critical temperature rise and thermal postbuckling path is negligible. Moreover, by increasing the sector angle, the effect of BCs of straight edges vanishes, and the critical temperature rise and thermal postbuckling curves of for BCs of CSCS and SCSC approach those for CCCC and SSSS ones. [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]

Vibration and buckling analysis of a magneto-electro-elastic sandwich Timoshenko beam with a porous core and poly-vinylidene fluoride (PVDF) matrix reinforced by carbon nanotubes (CNTs) is considered as face layers and material properties of CNTs and PVDF are assumed to be temperature-dependent. Different CNT distribution patterns including uniform distribution, AV (which top and bottom face sheets have functionally graded-A (FG-A) and functionally graded-V (FG-V) CNT distribution patterns, respectively) and VA patterns are employed. The governing equations of motion are derived based on Timoshenko beam theory, and Navier's solution is used to solve these equations. The sandwich beam resting on a Pasternak foundation and face layers are subjected to electric and magnetic potentials. The effect of different parameters such as porosity coefficient, electric and magnetic potential, parameters of foundation, and geometrical parameters are investigated on vibration and buckling behavior of the sandwich beam. Numerical results of this paper show that porosity distribution has a significant effect on the stiffness of the sandwich beam. The results can be used for future analysis of magneto-electro-mechanical sandwich systems as actuators and sensors. [ABSTRACT FROM AUTHOR]

Thermal postbuckling analysis is presented for graphene-reinforced composite (GRC) laminated cylindrical shells under a uniform temperature field. The GRC layers are arranged in a functionally graded (FG) graphene reinforcement pattern by varying the graphene volume fraction in each GRC layer. The GRCs possess temperature dependent and anisotropic material properties and the extended Halpin-Tsai model is employed to evaluate the GRC material properties. The governing equations are based on a higher order shear deformation shell theory and include the von Kármán-type kinematic nonlinearity and the thermal effects. A singular perturbation method in conjunction with a two-step perturbation approach is applied to determine the thermal postbuckling equilibrium path for a GRC shell with or without geometric imperfection. An iterative scheme is developed to obtain numerical thermal buckling temperatures and thermal postbuckling load-deflection curves for the shells. The results reveal that the FG-X piece-wise FG graphene distribution can enhance the thermal postbuckling capacity of the shells when the shells are subjected to a uniform temperature loading. [ABSTRACT FROM AUTHOR]

In this article, based on high-order sandwich panel theory and modified strain gradient theory, free vibration analysis of a micro-magneto-electro-elastic sandwich panel with a transversely flexible core and functionally graded carbon nanotube–reinforced nanocomposite face sheets is investigated. Also, the influences of temperature-dependent material properties and various circuit boundary conditions such as open and closed are considered in this study. Carbon nanotubes are arranged in longitudinal direction inside polyvinylidene fluoride matrix with various functionally graded (FG) distributions such as uniform, FG-V, FG-A, FG-X, and FG-O in the face sheets. The generalized rule of mixture is employed to predict mechanical, electrical, magnetic, and thermal properties of micro-sandwich composite panel. The classical shell theory and an elasticity high-order theory are used for the face sheets and the core, respectively. Then, the governing equations of motion are derived using Hamilton’s principle. In this article, the influences of the volume fraction, the various distributions of carbon nanotubes, the multi-physical fields, open- and closed-circuit boundary conditions, the material length scale parameters, different face sheet and core thicknesses, and temperature changes on the natural frequency are investigated, and the obtained results show that these influences play an important role in the natural frequencies and can be used in order to prevent the resonance phenomenon and also for manufacturing process design and optimization of micro-magneto-electro-elastic composite sandwich cylindrical panels. [ABSTRACT FROM AUTHOR]

In this paper, we study the nonlinear dynamic response of higher order shear deformable sandwich functionally graded circular cylindrical shells with outer surface-bonded piezoelectric actuator on elastic foundations subjected to thermo-electro-mechanical and damping loads. The sigmoid functionally graded material shells are made of the metal–ceramic–metal layers with temperature-dependent material properties. The governing equations are established based on Reddy’s third-order shear deformation theory using the stress function, the Galerkin method and the fourth-order Runge–Kutta method. Numerical results are given to demonstrate the influence of geometrical parameters, material properties, imperfection, elastic foundations, and thermo-electro-mechanical and damping loads on the nonlinear dynamic response of the shells. Accuracy of the present formulation is shown by comparing the results of numerical examples with the ones available in literature. [ABSTRACT FROM AUTHOR]

Assessing the stability of steel building frames exposed to fire conditions is challenging because of the need to consider the elevated temperature properties of steel, nonuniform heating of structural members, and large deformational demands on the frames. This challenge is further intensified if the stability of the frame is also influenced by the lateral forces of an earthquake that preceded the fire. Although there has been significant progress recently in simulating the response of frames using finite-element methods, there is a need for computationally efficient tools that would minimize the modeling effort and allow for accurate and rapid assessment so that a large number of simulations can be conducted. To this end, the present study aims to develop a framework for conducting a stability analysis of steel columns subjected to demands imposed by lateral loading followed by fire. A nonlinear formulation is proposed to assess the stability of W-shaped steel columns under multihazard loading scenarios. Results from the proposed formulation show good agreement with available strength design equations of steel columns at ambient and elevated temperatures. This computationally efficient tool can be used to investigate the effects of a wide variety of variables on the stability of steel columns subjected to fire and fire following earthquakes. [ABSTRACT FROM AUTHOR]

Based on Reddy’s third-order shear deformation plate theory, the nonlinear dynamic response and vibration of imperfect functionally graded carbon nanotube-reinforced composite (FG-CNTRC) plates on elastic foundations subjected to dynamic loads and temperature are presented. The plates are reinforced by single-walled carbon nanotubes which vary according to the linear functions of the plate thickness. The plate’s effective material properties are assumed to depend on temperature and estimated through the rule of mixture. By applying the Airy stress function, Galerkin method and fourth-order Runge–Kutta method, nonlinear dynamic response and natural frequency for imperfect FG-CNTRC plates are determined. In numerical results, the influences of geometrical parameters, elastic foundations, initial imperfection, dynamic loads, temperature increment, and nanotube volume fraction on the nonlinear vibration of FG-CNTRC plates are investigated. The obtained results are validated by comparing with those of other authors. [ABSTRACT FROM PUBLISHER]

The nonlinear dynamics of an eccentrically stiffened functionally graded material (ES-FGM) plates resting on the elastic Pasternak foundations subjected to mechanical and thermal loads is considered in this article. The plates are reinforced by outside stiffeners with temperature-dependent material properties in two cases: uniform temperature rise and through the thickness temperature gradient. Both stiffeners and plate are deformed under temperature. Using Reddy’s third-order shear deformation plate theory, stress function, Galerkin and fourth-order Runge–Kutta methods, the effects of material and geometrical properties, temperature-dependent material properties, elastic foundations, and stiffeners on the nonlinear dynamic response of the ES-FGM plate in thermal environments are studied and discussed. Some obtained results are validated by comparing with those in the literature. [ABSTRACT FROM PUBLISHER]

This article investigates the nonlinear stability of eccentrically stiffened moderately thick plates made of functionally graded materials (FGM) subjected to inplane compressive, thermo-mechanical loads. The equilibrium and compatibility equations for the moderately thick plates are derived by using the first-order shear deformation theory of plates, taking into account both the geometrical nonlinearity in the von Karman sense and initial geometrical imperfections, temperaturedependent properties with Pasternak type elastic foundations. By applying the Galerkin method and using a stress function, the effects of material and geometrical properties, temperature-dependent material properties, elastic foundations, boundary conditions, and eccentric stiffeners on the buckling and post-buckling loading capacity of the eccentrically stiffened moderately thick FGM plates in thermal environments are analyzed and discussed. [ABSTRACT FROM AUTHOR]

The authors of this article investigate the nonlinear stability of axisymmetric functionally graded annular spherical shells with temperature-dependent material properties subjected to thermo-mechanical loads and resting on elastic foundations. Equilibrium and compatibility equations are derived by using the classical thin shell theory in terms of the shell deflection and the stress function. Approximate analytical solutions are assumed to satisfy simply supported boundary conditions and Galerkin method is applied to obtain the closed-form of load–deflection paths. An analysis is carried out to show the effects of material and geometrical properties and combination of loads on the stability of the shells. [ABSTRACT FROM PUBLISHER]

The knowledge of the fracture strength of solids from room temperature to melting point is not only important for practical application but also useful for the understanding of the failure mechanisms of materials at elevated temperatures. In the present work, an apparatus for high-temperature mechanical testing has been developed and described in detail. The load-displacement curves of the bulk polycrystalline alumina from room temperature to melting point are measured on a three-point bending configuration. The bending strength is calculated from the updated formula of material mechanics which includes the temperature-dependent thermal expansions of the fixture and specimen. The brittle-ductile transition temperature of polycrystalline alumina is identified and is ~1500°C. The strength-temperature curves below and above brittle-ductile transition temperature are convex and concave, respectively. Strength is sensitive to defects at lower temperatures. Not only the values also the temperature dependence of the strength are affected by impurity and microflaws significantly. This is different from Young's modulus whose temperature dependence is insensitive to microstructure of materials. [ABSTRACT FROM AUTHOR]

Elastoplastic analysis of a composite cylinder, consisting of an isotropic elastic inclusion surrounded by orthotropic matrix, is conducted via numerical parametric studies for examining its residual stress under thermal cycles. The matrix is assumed to be elastically and plastically orthotropic, and all of its material properties are temperature-dependent (TD). The Hill's anisotropic plasticity material model is adopted. The interface between the inclusion and matrix is perfectly bonded, and the outer boundary of the cylinder is fully constrained. A quasi-static, uniform temperature field is applied to the cylinder, which is analyzed under the plane-strain assumption. The mechanical responses of the composite cylinder are strongly affected by the material symmetry and temperature-dependent material properties. When the temperature-independent material properties are assumed, larger internal stresses at the loading phase are predicted. Furthermore, considering only yield stress being temperature dependent may be insufficient since other TD material parameters may also affect the stress distributions. In addition, plastic orthotropy inducing preferential yielding along certain directions leads to complex residual stress distributions when material properties are temperature-dependent. [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]