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Sensor Review provides an update on photoelastic and thermoelastic stress analysis.

The goal of this work is to create a computational finite element model to perform thermoelastic stress analysis (TSA) with the usage of a non-ideal load frequency, containing the effects of the material thermal properties.

Throughout this document, the methodology of the model is presented first, followed by the procedure and results. The last part is reserved to results, discussion and conclusions.

This work had the main goal to create a model to perform TSA with the usage of non-ideal loading frequencies, considering the materials’ thermal properties. Loading frequencies out of the ideal range were applied and the model showed capable of good results. The created model reproduced acceptably the TSA, with the desired conditions.

This work creates a model to perform TSA with the usage of non-ideal loading frequencies, considering the materials’ thermal properties.

Maintenance is one of the most critical and expensive operations during the life cycle of metallic structures, in particular in the aeronautic industry. However, early detection of fatigue cracks is one of the most demanding operations in global maintenance procedures. In this context, non-destructive testing using image techniques may represent one of the best solutions in such situations, especially thermal stress analyses (TSA) using infrared thermography. The purpose of this paper is to access and characterize the main stress profile calculated through temperature variation, for different load frequencies.

In this paper, a cyclic load is applied to an aluminum sample component while infrared thermal image is being acquired. According to the literature and experiments, a cyclic load applied to a material results in cyclic temperature variation.

Frequency has been shown to be an important parameter in TSA evaluations, increasing the measured stress profile amplitude. The loading stimulation frequency and the maximum stress recorded show a good correlation (R² higher than 0.995). It was verified that further tests and modeling should be performed to fully comprehend the influence of load frequency and to create a standard to conduct thermal stress tests.

This work revealed that the current infrared technology is capable of reaching far more detailed thermal and spatial resolution than the one used in the development of TSA models. Thus, for the first time the influence of mechanical load frequency in the thermal profiles of TSA is visible and consequentially the measured mechanical stress.

In this study, the effect of Friction Stir Welding on a 6061 aluminium alloy reinforced with 20% of alumina particles metal matrix composite was analysed. The sheets were joined by employing a tool rotating speed of 700 RPM and a welding speed of 250 mm/min. The optical and scanning electron microscopy observations performed on the different zones of FSW joints cross section revealed the different structures of the nugget, the thermo‐mechanical affected zone and the heat affected zones thanks to the difference in reinforcing particles dimensions as a consequence of friction process. After FSW the material was aged in a 3.5% NaCl solution for 1, 10 and 90 days. The aim of this work is to apply thermoelastic stress analysis to the study of crack formation and propagation of friction stir welded MMC sheets, during cyclic fatigue tests. Fatigue tests were carried out under the axial total stress‐amplitude control mode with R=omin/omax = 0.1 using a resonant electro‐mechanical testing machine (TESTRONICTM 50 25 KN by RUMUL (SUI)). All the mechanical tests were performed on as‐FSW and aged samples up to failure. The TSA measurement system allowed the crack evolution to be observed in real‐time during fatigue cycles and stress fields to be derived on the specimens from the temperature variation measured.

Composite materials are increasingly used in the structural and mechanical fields, thanks to their high strength‐to‐weight ratios and the possibility of tailoring them to meet specific requirements. This study is focused on the damage to a glass fiber reinforced composite under different loading conditions. The aim is to find, by coupling mechanical tests with thermal analyses, a damage parameter, able to define the damage initiation in the studied material.

The object of this work is a glass‐fiber reinforced plastic (GFRP) laminate. To study the damage of this material under different loading conditions, static, dynamic and fatigue tests were carried out. During these tests, the surface temperature of the specimens was monitored by means of an IR‐camera. In the dynamic tests, a D‐mode (dissipation mode) analysis was also performed allowing the dissipated energy to be determined.

In the literature, thermography is an experimental technique which has always been applied to the study of homogeneous materials. Results obtained from the proposed experimental tests on this GFRP composite show how this practice can be applied also to this kinds of materials, to identify their damage initiation. From these observations, the results can be used to definite a stress corresponding to the damage initiation, which can be related to the fatigue behavior, and useful in design stage with these materials.

This paper provides for a useful tool to understand and predict fatigue behavior of a GFRP composite, from thermographic observations. Applications of thermography to the study of composite materials is an innovative research field, and the presented results seems satisfactory and promising for further experimental investigations.

This paper gives a bibliographical review of the finite element methods (FEMs) applied to the analysis of ceramics and glass materials. The bibliography at the end of the paper contains references to papers, conference proceedings and theses/dissertations on the subject that were published between 1977‐1998. The following topics are included: ceramics – material and mechanical properties in general, ceramic coatings and joining problems, ceramic composites, ferrites, piezoceramics, ceramic tools and machining, material processing simulations, fracture mechanics and damage, applications of ceramic/composites in engineering; glass – material and mechanical properties in general, glass fiber composites, material processing simulations, fracture mechanics and damage, and applications of glasses in engineering.

The purpose of this paper is to discuss the problem of thermoelasticity with voids under the gravity field in the context of a general form of heat conduction equation with some particular cases. The normal mode method used is to obtain the physical quantities.

The analytical method used was the normal mode.

Numerical results for the physical quantities are presented graphically and the results are analyzed thereafter. The comparisons are established between the theories for the physical quantities during the constant time and gravity and were shown graphically.

In the present work, the authors shall establish the general form for the heat conduction equation which contains the seven theories as well as the special cases in thermoelasticity with voids. The problem is very important in many dynamical systems.

Gives a bibliographical review of the finite element analyses of sandwich structures from the theoretical as well as practical points of view. Both isotropic and composite materials are considered. Topics include: material and mechanical properties of sandwich structures; vibration, dynamic response and impact problems; heat transfer and thermomechanical responses; contact problems; fracture mechanics, fatigue and damage; stability problems; special finite elements developed for the analysis of sandwich structures; analysis of sandwich beams, plates, panels and shells; specific applications in various fields of engineering; other topics. The analysis of cellular solids is also included. The bibliography at the end of this paper contains 655 references to papers, conference proceedings and theses/dissertations dealing with presented subjects that were published between 1980 and 2001.

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The purpose of the study is to perform elastic stress and deformation analysis of a functionally graded hollow disk under different conditions (rotation, gravity, internal pressure, temperature with variable heat generation) and their combinations.

The classical method of solution, Navier's equation, is used to solve the governing equation. The analysis considers thermal and mechanical boundary conditions and takes into account the variation of material properties according to a power law function of the radius of the disk and grading parameter.

The findings of the study reveal distinct trends and behaviors based on different grading parameters. The influence of gravity is found to be negligible, resulting in similar patterns to the pure rotation case. Variable heat generation introduces non-linear temperature profiles and higher displacements, with stress values influenced by grading parameters.

The study provides valuable insights into the behavior of displacement and stresses in hollow disks, offering a deeper understanding of their mechanical response under varying conditions. These insights can be useful in the design and analysis of functionally graded hollow disks in various engineering applications.

The originality and value of this study lies in the consideration of various loading combinations of rotation, gravity, internal pressure and temperature with variable heat generation. Furthermore, the study of effect of various angular rotations, temperatures and pressures expands the understanding of the mechanical behavior of such structures, contributing to the existing body of knowledge in the field.