Journal articles: 'Metallo-thermomechanical finite element model'

1

Das, S., Eric J. Palmiere, and I. C. Howard. "Modelling Recrystallisation during Thermomechanical Processing Using CAFE." Materials Science Forum 467-470 (October 2004): 623–28. http://dx.doi.org/10.4028/www.scientific.net/msf.467-470.623.

Full text

Abstract:

A common feature that stimulates modelling efforts across the various physical sciences is that complex microscopic behaviour underlies apparently simple macroscopic effects. Mathematical formulations attempt to capture the initial and evolving microstructural entities either implicitly or explicitly and link their effects to measurable macroscopic variables such as load or stress by averaging out any microscopic fluctuations. The implicit formulations that ignore the inherent spatial heterogeneity in the deforming domain form the basis of constitutive models for input to finite element (FE) systems. On the other hand, explicit formulations to capture and link microstructural entities rely on narrowing down the size of each finite element, thereby increasing the number of finite elements in the deforming domain, an effect accompanied by a rapid growth in computational time. The model described here, Cellular Automata based Finite Elements (CAFE), utilises the Cellular Automata technique to represent initial and evolving microstructural features (e.g., dislocation densities, grain sizes, etc.) in C-Mn steels at an appropriate length scale by linking the macro-scale process variables obtained using an overlying finite element mesh. Differences will be illustrated between single and two-pass hot rolling experiments.

APA, Harvard, Vancouver, ISO, and other styles

2

Burlayenko, Vyacheslav N. "Modelling Thermal Shock in Functionally Graded Plates with Finite Element Method." Advances in Materials Science and Engineering 2016 (2016): 1–12. http://dx.doi.org/10.1155/2016/7514638.

Full text

Abstract:

Thermomechanical behavior and crack propagation in a functionally graded metal/ceramic plate undergoing thermal shock are analyzed by using the finite element method. A two-dimensional plane strain functionally graded finite element has been developed within the ABAQUS software environment for this purpose. An actual material gradation has been accomplished by sampling material quantities directly at the Gauss points of the element via programming appropriate user-defined subroutines. The virtual crack closure technique is used to model a crack growth under thermal loading. Contact possible between crack lips during the crack advance is taken into account in thermomechanical simulations as well. The paper shows that the presented finite element model can be applied to provide an insight into the thermomechanical respond and failure of the metal/ceramic plate.

APA, Harvard, Vancouver, ISO, and other styles

3

CELENTANO, D., S. OLLER, and E. OÑATE. "A finite element model for thermomechanical analysis in casting processes." Le Journal de Physique IV 03, no. C7 (November 1993): C7–1171—C7–1180. http://dx.doi.org/10.1051/jp4:19937182.

Full text

APA, Harvard, Vancouver, ISO, and other styles

4

Wriggers, P., and C. Miehe. "Contact constraints within coupled thermomechanical analysis—A finite element model." Computer Methods in Applied Mechanics and Engineering 113, no. 3-4 (March 1994): 301–19. http://dx.doi.org/10.1016/0045-7825(94)90051-5.

Full text

APA, Harvard, Vancouver, ISO, and other styles

5

Rakotomalala, R., P. Joyot, and M. Touratier. "Arbitrary Lagrangian-Eulerian thermomechanical finite-element model of material cutting." Communications in Numerical Methods in Engineering 9, no. 12 (December 1993): 975–87. http://dx.doi.org/10.1002/cnm.1640091205.

Full text

APA, Harvard, Vancouver, ISO, and other styles

6

Zivkovic, Dragoljub, Dragan Milcic, Milan Banic, and Pedja Milosavljevic. "Thermomechanical finite element analysis of hot water boiler structure." Thermal Science 16, suppl. 2 (2012): 387–98. http://dx.doi.org/10.2298/tsci120503177z.

Full text

Abstract:

The paper presents an application of the Finite Elements Method for stress and strain analysis of the hot water boiler structure. The aim of the research was to investigate the influence of the boiler scale on the thermal stresses and strains of the structure of hot water boilers. Results show that maximum thermal stresses appear in the zone of the pipe carrying wall of the first reversing chamber. This indicates that the most critical part of the boiler are weld spots of the smoke pipes and pipe carrying plate, which in the case of significant scale deposits can lead to cracks in the welds and water leakage from the boiler. The nonlinear effects were taken into account by defining the bilinear isotropic hardening model for all boiler elements. Temperature dependency was defined for all relevant material properties, i. e. isotropic coefficient of thermal expansion, Young?s modulus, and isotropic thermal conductivity. The verification of the FEA model was performed by comparing the measured deformations of the hot water boiler with the simulation results. As a reference object, a Viessmann - Vitomax 200 HW boiler was used, with the installed power of 18.2 MW. CAD modeling was done within the Autodesk Inventor, and stress and strain analysis was performed in the ANSYS Software.

APA, Harvard, Vancouver, ISO, and other styles

7

Bergman, G., and M. Oldenburg. "A finite element model for thermomechanical analysis of sheet metal forming." International Journal for Numerical Methods in Engineering 59, no. 9 (February 3, 2004): 1167–86. http://dx.doi.org/10.1002/nme.911.

Full text

APA, Harvard, Vancouver, ISO, and other styles

8

Fu, C., D. L. McDowell, and I. C. Ume. "A Finite Element Procedure of a Cyclic Thermoviscoplasticity Model for Solder and Copper Interconnects." Journal of Electronic Packaging 120, no. 1 (March 1, 1998): 24–34. http://dx.doi.org/10.1115/1.2792281.

Full text

Abstract:

A finite element procedure using a semi-implicit time-integration scheme has been developed for a cyclic thermoviscoplastic constitutive model for Pb-Sn solder and OFHC copper, two common metallic constituents in electronic packaging applications. The scheme has been implemented in the commercial finite element (FE) code ABAQUS (1995) via the user-defined material subroutine, UMAT. Several single-element simulations are conducted to compare with previous test results, which include monotonic tensile tests, creep tests, and a two-step ratchetting test for 62Sn36Pb2Ag solder; a nonproportional axial-torsional test and a thermomechanical fatigue (TMF) test for OFHC copper. At the constitutive level, we also provide an adaptive time stepping algorithm, which can be used to improve the overall computation efficiency and accuracy especially in large-scale FE analyses. We also compare the computational efforts of fully backward Euler and the proposed methods. The implementation of the FE procedure provides a guideline to apply user-defined material constitutive relations in FE analyses and to perform more sophisticated thermomechanical simulations. Such work can facilitate enhanced understanding thermomechanical reliability issue of solder and copper interconnects in electronic packaging applications.

APA, Harvard, Vancouver, ISO, and other styles

9

Wang, Jun, Weihong Zhang, Jihong Zhu, Yingjie Xu, Xiaojun Gu, and Ziad Moumni. "Finite element simulation of thermomechanical training on functional stability of shape memory alloy wave spring actuator." Journal of Intelligent Material Systems and Structures 30, no. 8 (March 21, 2019): 1239–51. http://dx.doi.org/10.1177/1045389x19831356.

Full text

Abstract:

Pre-service thermomechanical training is of great significance to achieve functional stability for shape memory alloy device. This article presents a finite element simulation of the training behavior of a shape memory alloy wave spring actuator using a thermomechanically coupled and finite-strain shape memory alloy model (Wang et al., 2017a). The model is implemented into ABAQUS/Explicit by means of a user-defined material subroutine VUMAT. The introduction of a finite-Hencky-strain return-mapping integration scheme substantially improves the numerical efficiency and stability. Model predictions are validated against the experimental data. The good agreement between both demonstrates the capabilities of the model of well describing the training behavior of shape memory alloy when subjected to large cyclic thermomechanical loading. Simulation results illustrate several primary thermomechanical characteristics during training process, such as the expansion of the phase transformation zone, the accumulation of the residual deformation, and the concentration of the internal stress. The present finite element approach provides a powerful tool in design and optimization of shape memory alloy wave spring actuator, especially to improve the geometric precision and to enhance the two-way shape memory effect.

APA, Harvard, Vancouver, ISO, and other styles

10

Lagoudas, D. C., J. G. Boyd, and Z. Bo. "Micromechanics of Active Composites With SMA Fibers." Journal of Engineering Materials and Technology 116, no. 3 (July 1, 1994): 337–47. http://dx.doi.org/10.1115/1.2904297.

Full text

Abstract:

The study of the effective thermomechanical response of active fibrous composites with shape memory alloy (SMA) fibers is the subject of this work. A 3-D constitutive response for the SMA fibers is formulated first. To model thermomechanical loading path dependence, an incremental approach is used assuming that within each stress and temperature increment the volume fraction of the martensitic phase remains constant in the SMA fibers. The Mori-Tanaka averaging scheme is then used to give an estimate of the instantaneous effective thermomechanical properties in terms of the thermomechanical properties of the two phases and martensitic volume fraction. A unit cell model for a periodic active composite with cubic and hexagonal arrangement of fibers is also developed to study the effective properties using finite element analysis. It is found that since the fibers and not the matrix undergo the martensitic phase transformation that induces eigenstrains, the Mori-Tanaka averaging scheme accurately models the thermomechanical response of the composite, relative to the finite element analysis, for different loading paths. Specific results are reported for the composite pseudoelastic and shape memory effect for an elastomeric matrix continuous SMA fiber composite.

APA, Harvard, Vancouver, ISO, and other styles

11

Qin, Qin, Shu Shang, Diping Wu, and Yong Zang. "Comparative Analysis of Bulge Deformation between 2D and 3D Finite Element Models." Advances in Mechanical Engineering 6 (January 1, 2014): 942719. http://dx.doi.org/10.1155/2014/942719.

Full text

Abstract:

Bulge deformation of the slab is one of the main factors that affect slab quality in continuous casting. This paper describes an investigation into bulge deformation using ABAQUS to model the solidification process. A three-dimensional finite element analysis model of the slab solidification process has been first established because the bulge deformation is closely related to slab temperature distributions. Based on slab temperature distributions, a three-dimensional thermomechanical coupling model including the slab, the rollers, and the dynamic contact between them has also been constructed and applied to a case study. The thermomechanical coupling model produces outputs such as the rules of bulge deformation. Moreover, the three-dimensional model has been compared with a two-dimensional model to discuss the differences between the two models in calculating the bulge deformation. The results show that the platform zone exists in the wide side of the slab and the bulge deformation is affected strongly by the ratio of width-to-thickness. The indications are also that the difference of the bulge deformation for the two modeling ways is little when the ratio of width-to-thickness is larger than six.

APA, Harvard, Vancouver, ISO, and other styles

12

Shen, Hong, Jun Hu, and Zhenqiang Yao. "Mixed-dimensional coupling modeling for laser forming process." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 228, no. 16 (February 20, 2014): 2950–59. http://dx.doi.org/10.1177/0954406214525136.

Full text

Abstract:

Efficient laser forming modeling for industrial application is still in the developing stage and many researchers are in the process of modifying it. Conventional three-dimensional finite element models are still expensive on computational time. In this paper, a finite element model adopting a shell-solid coupling technique is developed for the thermomechanical analysis of laser forming process. In the shell-solid coupling method, an additional shell element plane is utilized to transfer heat flux and displacement from the solid elements to the shell elements. The effects of the additional interface shell element thickness on temperature distribution and final distortion are investigated. The presented shell-solid coupling method is evaluated by the results of three-dimensional simulations and experimental data.

APA, Harvard, Vancouver, ISO, and other styles

13

Baghani, Mostafa, Reza Naghdabadi, and Jamal Arghavani. "A large deformation framework for shape memory polymers: Constitutive modeling and finite element implementation." Journal of Intelligent Material Systems and Structures 24, no. 1 (September 5, 2012): 21–32. http://dx.doi.org/10.1177/1045389x12455728.

Full text

Abstract:

Shape memory polymers commonly experience both finite deformations and arbitrary thermomechanical loading conditions in engineering applications. This motivates the development of three-dimensional constitutive models within the finite deformation regime. In the present study, based on the principles of continuum thermodynamics with internal variables, a three-dimensional finite deformation phenomenological constitutive model is proposed taking its basis from the recent model in the small strain regime proposed by Baghani et al. (2012). In the constitutive model derivation, a multiplicative decomposition of the deformation gradient into elastic and inelastic stored parts (in each phase) is adopted. Moreover, employing the mixture rule, the Green–Lagrange strain tensor is related to the rubbery and glassy parts. In the constitutive model, the evolution laws for internal variables are derived during both cooling and heating thermomechanical loadings. Furthermore, we present the time-discrete form of the proposed constitutive model in the implicit form. Using the finite element method, we solve several boundary value problems, that is, tension and compression of bars and a three-dimensional beam made of shape memory polymers, and investigate the model capabilities as well as its numerical counterpart. The model is validated by comparing the predicted results with experimental data reported in the literature that shows a good agreement.

APA, Harvard, Vancouver, ISO, and other styles

14

Krivenko, Olha, and Yurii Vorona. "Comparative Analysis of Nonlinear Deformation and Buckling of Thin Elastic Shells of Step-Variable Thickness." Strength of Materials and Theory of Structures, no. 108 (May 30, 2022): 107–18. http://dx.doi.org/10.32347/2410-2547.2022.108.107-118.

Full text

Abstract:

A comparative analysis of finite element models and methods for solving complex problems of geometrically nonlinear deformation, buckling and post-buckling behavior of thin shells of stepwise variable thickness is carried out. An approach based on the use of the moment scheme of finite elements is considered. The features of using the software suite LIRA and integrated software system SCAD for solving the assigned problems are also provided. Thin and medium thickness shells are considered. They can have different geometric features in thickness and be under the action of static thermomechanical loads. A technique for solving these problems with the help of an efficient refined approach is presented. The technique is based on the general methodological positions of the three-dimensional theory of thermoelasticity and the use of the finite element moment scheme. With this approach, the approximation through the shell thickness is carried out by a single universal spatial finite element. The element can be modified in different portions of the shell with a step-variable thickness. It can be located eccentrically relative to the middle surface of the casing and can change its dimensions in the direction of the shell thickness. Such a unified approach made it possible to create a unified designed finite element model of a shell of an inhomogeneous geometric structure under the combined action of a thermomechanical load. A comparative analysis of the application of three finite element approaches for problems of geometrically nonlinear deformation and buckling of shells of stepwise variable thickness is carried out.

APA, Harvard, Vancouver, ISO, and other styles

15

Li, Chunsheng, and Brian G. Thomas. "Thermomechanical finite-element model of shell behavior in continuous casting of steel." Metallurgical and Materials Transactions B 35, no. 6 (December 2004): 1151–72. http://dx.doi.org/10.1007/s11663-004-0071-z.

Full text

APA, Harvard, Vancouver, ISO, and other styles

16

Parizek, Byron R., Richard B. Alley, and Douglas R. MacAyeal. "The PSU/UofC finite-element thermomechanical flowline model of ice-sheet evolution." Cold Regions Science and Technology 42, no. 2 (July 2005): 145–68. http://dx.doi.org/10.1016/j.coldregions.2004.12.006.

Full text

APA, Harvard, Vancouver, ISO, and other styles

17

Darbha, K., J. H. Okura, S. Shetty, A. Dasgupta, T. Reinikainen, J. Zhu, and J. F. J. M. Caers. "Thermomechanical Durability Analysis of Flip Chip Solder Interconnects: Part 2—With Underfill." Journal of Electronic Packaging 121, no. 4 (December 1, 1999): 237–41. http://dx.doi.org/10.1115/1.2793846.

Full text

Abstract:

The effect of underfill material on reliability of flip chip on board (FCOB) assemblies is investigated in this study by using two-dimensional and three-dimensional finite element simulations under thermal cycling stresses from −55°C to 80°C. Accelerated testing of FCOB conducted by the authors reveals that the presence of underfill can increase the fatigue durability of solder interconnects by two orders of magnitude. Similar data has been extensively reported in the literature. It is the intent of this paper to develop a generic and fundamental predictive model that explains this trend. While empirical models have been reported by other investigators based on experimental data, the main drawback is that many of these empirical models are not truly predictive, and can not be applied to different flip chip architectures using different underfills. In the proposed model, the energy-partitioning (EP) damage model is enhanced in order to capture the underlying mechanisms so that a predictive capability can be developed. A two-dimensional finite element model is developed for stress analysis. This model accounts for underfill over regions of solder in an approximate manner by using overlay elements, and is calibrated using a three-dimensional finite element model. The model constant for the enhanced EP model is derived by fitting model predictions (combination of two-dimensional and three-dimensional model results) to experimental results for a given temperature history. The accuracy of the enhanced EP model is then verified for a different loading profile. The modeling not only reveals the influence of underfill material on solder joint durability, but also provides the acceleration factor to assess durability under life cycle environment, from accelerated test results. Experimental results are used to validate the trends predicted by the analytical model. The final goal is to define the optimum design and process parameters of the underfill material in FCOB assemblies in order to extend the fatigue endurance of the solder joints under cyclic thermal loading environments.

APA, Harvard, Vancouver, ISO, and other styles

18

Wu, Wenhua, Ping Hu, and Guozhe Shen. "Thermomechanical-Phase Transformation Simulation of High-Strength Steel in Hot Stamping." Mathematical Problems in Engineering 2015 (2015): 1–12. http://dx.doi.org/10.1155/2015/982785.

Full text

Abstract:

The thermomechanical-phase transformation coupled relationship of high-strength steel has important significance in forming the mechanism and numerical simulation of hot stamping. In this study a new numerical simulation module of hot stamping is proposed, which considers thermomechanical-transformation multifield coupled nonlinear and large deformation analysis. In terms of the general shell finite element and 3D tetrahedral finite element analysis methods related to temperature, a coupled heat transmission model for contact interfaces between blank and tools is proposed. Meanwhile, during the hot stamping process, the phase transformation latent heat is introduced into the analysis of temperature field. Next the thermomechanical-transformation coupled constitutive models of the hot stamping are considered. Static explicit finite element formulae are adopted and implemented to perform the full numerical simulations of the hot stamping process. The hot stamping process of typical U-shaped and B-pillar steel is simulated using the KMAS software, and a strong agreement comparison between temperature, equivalent stress, and fraction of martensite simulation and experimental results indicates the validity and efficiency of the hot stamping multifield coupled constitutive models and numerical simulation software KMAS. The temperature simulated results also provide the basic guide for the optimization designs of cooling channels in tools.

APA, Harvard, Vancouver, ISO, and other styles

19

Koohbor, B., and S. Serajzadeh. "Thermomechanical behaviours of strip and work-rolls in cold rolling process." Journal of Strain Analysis for Engineering Design 46, no. 8 (August 22, 2011): 794–804. http://dx.doi.org/10.1177/0309324711417693.

Full text

Abstract:

A finite element analysis was developed to determine thermomechanical behaviours of strip and work-roll during cold rolling process under practical rolling conditions. The velocity field was first obtained using a rigid-plastic finite element formulation and then it was used to assess the strain and stress distributions within the strip and at the same time, a thermal finite element model based on streamline upwind Petrov–Galerkin scheme was employed to predict temperature distribution within the metal being rolled. In the next stage, the predicted temperature and stress fields at the contact region of strip/work-roll were employed as the boundary conditions to evaluate the thermomechanical behaviour of the work-roll while the effect of back-up rolls was also considered in the mechanical part of the analysis. The model is shown to provide a proper insight for studying the deformation of strip and work-roll during high speed cold rolling process with a relatively low computational cost.

APA, Harvard, Vancouver, ISO, and other styles

20

Leppänen, Anton, Asko Kumpula, Joona Vaara, Massimo Cattarinussi, Juho Könnö, and Tero Frondelius. "Thermomechanical Fatigue Analysis of Cylinder Head." Rakenteiden Mekaniikka 50, no. 3 (August 21, 2017): 182–85. http://dx.doi.org/10.23998/rm.64743.

Full text

Abstract:

The finite element simulation of a cylinder head has been carried out with Abaqus Standard using Z-mat material model, with thermal boundary conditions coming from combined conjugate heat transfer and gas-exchange simulations. The fatigue post-processing of results has been done with Z-post software using ONERA fatigue model. The resulting lifetime values have been found out to correspond well to observations from the field.

APA, Harvard, Vancouver, ISO, and other styles

21

Krivenko, Olha, Yurii Vorona, and Andrii Kozak. "Finite element analysis of nonlinear deformation, stability and vibrations of elastic thin-walled structures." Strength of Materials and Theory of Structures, no. 107 (October 29, 2021): 20–34. http://dx.doi.org/10.32347/2410-2547.2021.107.20-34.

Full text

Abstract:

Thin-walled shell-type structures are widely used in various branches of technology and industry. Such structures under operating conditions are usually exposed to various loads, including thermomechanical ones. Real shell structures, as a rule, have a complex shapes. To increase reliability, reduce material consumption, for technological reasons, they are designed as inhomogeneous systems in thickness. This causes a great and constant interest of engineers and designers in the problems of investigating the behavior of elastic thin-walled shell structures. The work is devoted to the method of analysis of geometrically nonlinear deformation, stability, post-buckling behavior and natural vibrations of thin elastic shells of complex shape and structure under the action of static thermomechanical loads. The unified design model has been created on the basis of the developed universal spatial finite element with introduced additional variable parameters. The model takes into account the multilayer material structure and geometric features for structural elements of the thin shell. The shells can be reinforced with ribs and cover plates, weakened by cavities, channels and holes, have sharp bends in the mid-surface. Such a uniform formulation made it possible to create a unified finite element model of the shells with an inhomogeneous structure. It is shown on a number of problems that the method presented in this article is an effective tool for analyzing geometrically nonlinear deformation, stability, post-buckling behavior and natural vibrations of thin elastic shells of an inhomogeneous structure under the action of static thermomechanical loads.

APA, Harvard, Vancouver, ISO, and other styles

22

Wang, Youshan, Yintao Wei, Xijin Feng, and Zhenhan Yao. "Finite Element Analysis of the Thermal Characteristics and Parametric Study of Steady Rolling Tires." Tire Science and Technology 40, no. 3 (October 1, 2012): 201–18. http://dx.doi.org/10.2346/tire.12.400304.

Full text

Abstract:

ABSTRACT This article presents a numerical thermomechanical analysis and parametric study of steady rolling tires that are treated as axisymmetric structures for simplification. Under periodic stress–strain cycles, during tire rolling, internal heat will be generated because of energy loss from the tire material. A general-purpose, finite element program is used to model this two-dimensional heat conduction with distributed, internal heat sources, whereas an in-house code for tire simulation performs the underlying three-dimensional structure and heat-generation rate analysis. The tire belts and carcasses are modeled using layer solid elements with transverse, isotropic, thermomechanical properties, whereas the rubber components are made of isotropic materials. The goal of this article is to develop a simple and easy methodology for simulating tire thermomechanical behavior. Furthermore, the parametric study for the highest shoulder temperature (HST), which is widely accepted as one of the triggers of tire failure, has been performed. The HST sensitivities to the selected parameters have been computed from the simulated temperature fields under different conditions, which provide a guidance to improve the tire structural, material, and pattern designs.

APA, Harvard, Vancouver, ISO, and other styles

23

Vasconcelos, Patricia, Adam Giessmann, João Dias-de-Oliveira, and António Andrade-Campos. "Heat Treatments Analysis of Steel Using Coupled Phase Field and Finite Element Methods." Key Engineering Materials 611-612 (May 2014): 117–24. http://dx.doi.org/10.4028/www.scientific.net/kem.611-612.117.

Full text

Abstract:

Steels are known for their remarkable mechanical properties being extensively used in industry. Furthermore, phase transformations in metals and alloys, particularly in steels, are widely studied due to their importance. The understanding of the microstructure evolution in this type of materials is vital to reproduce the thermomechanical behaviour and to create new materials. To analyse the thermomechanical behaviour of steel during phase transition of steels, a phase field model was coupled with a finite element model in order to simulate the heat treatment and microstructure evolution of austenite to pearlite/ferrite. The thermoelastoplastic constitutive equations for each phase were implemented through a user routine in commercial FE software. This procedure presents a more quantitative understanding of the phase transformation in steels and a deeper comprehension of the mechanical behaviour of these materials when subject to heat treatments.

APA, Harvard, Vancouver, ISO, and other styles

24

Basaran, C., C. S. Desai, and T. Kundu. "Thermomechanical Finite Element Analysis of Problems in Electronic Packaging Using the Disturbed State Concept: Part 1—Theory and Formulation." Journal of Electronic Packaging 120, no. 1 (March 1, 1998): 41–47. http://dx.doi.org/10.1115/1.2792284.

Full text

Abstract:

Accurate prediction of the thermomechanical cyclic behavior of joints and interfaces in semiconductor devices is essential for their reliable design. In order to understand and predict the behavior of such interfaces there is a need for improved and unified constitutive models that can include elastic, inelastic, viscous, and temperature dependent microstructural behavior. Furthermore, such unified material models should be implemented in finite element procedures so as to yield accurate and reliable predictions of stresses, strains, deformations, microcracking, damage, and number of cycles to failure due to thermomechanical loading. The main objective of this paper is to present implementation of such an unified constitutive model in a finite element procedure and its application to typical problems in electronic packaging; details of the constitutive model are given by Desai et al. (1995). Details of the theoretical formulation is presented in this Part 1, while its applications and validations are presented in Part 2, Basaran et al. (1998).

APA, Harvard, Vancouver, ISO, and other styles

25

Hernández, Maribel, Ricardo R. Ambriz, Christian García, and David Jaramillo. "The Thermomechanical Finite Element Analysis of 3003-H14 Plates Joined by the GMAW Process." Metals 10, no. 6 (May 27, 2020): 708. http://dx.doi.org/10.3390/met10060708.

Full text

Abstract:

The gas metal arc welding (GMAW) process was used to weld 3003-H14 plates under restricted and unrestricted thermal expansion. Experimental and numerical analysis were conducted to determine the relation between weld thermal cycles and residual stresses. A customized data acquisition system with K-type thermocouples was used to measure the weld thermal cycles, while residual stresses were determined by the hole drilling method. Thermo-mechanical simulation models for the two restricted conditions were implemented from the experimental data obtained. A double ellipse heat distribution geometry was used to model the heat moving source by using the finite element method. Thermal rates and peak temperatures were approximated by the finite element model with 2% difference, with respect to the experimental weld thermal cycles. Longitudinal and transverse normal residual stresses determined by the finite element model showed a good comparison with experimental measurements. The larger residual stresses were in the transverse direction for both clamping conditions, which indicated that working loading paths along the lateral direction of the welded plate are more influenced by the post-welding residual stresses.

APA, Harvard, Vancouver, ISO, and other styles

26

Zhao, Peng, Xiaozhao Li, Lihua Hu, Yun Wu, and Chenyang Zhang. "A Finite Element Model for Investigating Unsteady-State Temperature Distribution and Thermomechanical Behavior of Underground Energy Piles." Applied Sciences 12, no. 17 (August 23, 2022): 8401. http://dx.doi.org/10.3390/app12178401.

Full text

Abstract:

The underground energy geostructure represented by the energy pile is one of the key paths for the cooperative development of underground space and geothermal energy. Because of its advantages of low cost, high efficiency and no extra occupation of underground space, it has become a feasible alternative to the borehole heat exchanger. The change in the temperature field of the energy pile and its surrounding ground not only affects the geological environment but also influences the thermomechanical performance and the durability of the structure. However, the temporal and spatial unsteady-state temperature distribution of piles and surrounding rock under typical intermittent and unbalanced thermal load conditions is still unclear. In this paper, a finite element model was applied to analyze the unsteady-state temperature distribution, and the thermomechanical behavior of the energy pile group was developed and verified. The temperature field distribution of pile and surrounding rock under typical intermittent working and unbalanced thermal load conditions were determined. Moreover, the thermomechanical behavior characteristics of the energy pile group were investigated. Finally, the influences of pile layout on the thermomechanical behavior of the energy pile group were identified by designing six different scenarios. The results indicate that under typical intermittent operation conditions, the temperature of the energy pile and surrounding ground near the heat exchange pipe varies periodically. For areas with unbalanced cooling and heating loads, long-term operation of energy piles leads to thermal accumulation, and the maximum temperature of energy piles occurs in the first daily cycle. In summer/winter working conditions, the increase/decrease in pile temperature induces axial compression/tensile stress. When the pile group is partially used as the energy pile, the non-energy pile acts as the “anchor pile”, and it generates the added tensile stress.

APA, Harvard, Vancouver, ISO, and other styles

27

Han, Z. Q., W. Zhu, and B. C. Liu. "A thermomechanical finite element model for simulating the solidification process of squeeze casting." International Journal of Cast Metals Research 22, no. 1-4 (August 2009): 119–22. http://dx.doi.org/10.1179/136404609x367498.

Full text

APA, Harvard, Vancouver, ISO, and other styles

28

Belhocine, Ali. "Numerical investigation of a three-dimensional disc-pad model with and without thermal effects." Thermal Science 19, no. 6 (2015): 2195–204. http://dx.doi.org/10.2298/tsci141130072b.

Full text

Abstract:

This study aims to identify thermal effects in the structure and the contact behavior of a disc-pad assembly using a finite element approach. The first analysis is performed on the disc-pad model in the absence of thermal effects. The structural performance of the disc-pad model is predicted in terms of factors such as the deformation and Von Mises stress. Next, thermomechanical analysis is performed on the same disc-pad model with the inclusion of convection, adiabatic, and heat flux elements. The predicted temperature distribution, deformation, stress, and contact pressure are presented. The structural performance between the two analyses (mechanical and thermomechanical) is compared. This study can assist brake engineers in choosing a suitable analysis method to critically evaluate the structural and contact behavior of the disc brake assembly.

APA, Harvard, Vancouver, ISO, and other styles

29

Khalil, Walid, Alain Mikolajczak, Céline Bouby, and Tarak Ben Zineb. "A constitutive model for Fe-based shape memory alloy considering martensitic transformation and plastic sliding coupling: Application to a finite element structural analysis." Journal of Intelligent Material Systems and Structures 23, no. 10 (May 6, 2012): 1143–60. http://dx.doi.org/10.1177/1045389x12442014.

Full text

Abstract:

In this article, we propose a finite element numerical tool adapted to a Fe-based shape memory alloy structural analysis, based on a developed constitutive model that describes the effect of phase transformation, plastic sliding, and their interactions on the thermomechanical behavior. This model was derived from an assumed expression of the Gibbs free energy taking into account nonlinear interaction quantities related to inter- and intragranular incompatibilities as well as mechanical and chemical quantities. Two scalar internal variables were considered to describe the phase transformation and plastic sliding effects. The hysteretic and specific behavior patterns of Fe-based shape memory alloy during reverse transformation were studied by assuming a dissipation expression. The proposed model effectively describes the complex thermomechanical loading paths. The numerical tool derived from the implicit resolution of the nonlinear partial derivative constitutive equations was implemented into the Abaqus® finite element code via the User MATerial (UMAT) subroutine. After tests to verify the model for homogeneous and heterogeneous thermomechanical loadings, an example of Fe-based shape memory alloy application was studied, which corresponds to a tightening system made up of fishplates for crane rails. The results we obtained were compared to experimental ones.

APA, Harvard, Vancouver, ISO, and other styles

30

Zhang, X. Richard, and Xianfan Xu. "Finite Element Analysis of Pulsed Laser Bending: The Effect of Melting and Solidification." Journal of Applied Mechanics 71, no. 3 (May 1, 2004): 321–26. http://dx.doi.org/10.1115/1.1753268.

Full text

Abstract:

This work developes a finite element model to compute thermal and thermomechanical phenomena during pulsed laser induced melting and solidification. The essential elements of the model are handling of stress and strain release during melting and their retrieval during solidification, and the use of a second reference temperature, which is the melting point of the target material for computing the thermal stress of the resolidified material. This finite element model is used to simulate a pulsed laser bending process, during which the curvature of a thin stainless steel plate is altered by laser pulses. The bending angle and the distribution of stress and strain are obtained and compared with those when melting does not occur. It is found that the bending angle increases continulously as the laser energy is increased over the melting threshold value.

APA, Harvard, Vancouver, ISO, and other styles

31

Ali, Belhocine. "Finite Element Analysis of Automotive Disk Brake and Pad in Frictional Model Contact." International Journal of Manufacturing, Materials, and Mechanical Engineering 5, no. 4 (October 2015): 32–62. http://dx.doi.org/10.4018/ijmmme.2015100103.

Full text

Abstract:

The object of this work is to present a study of the thermomechanical behavior of the automobile disc brake during the braking phase. Then, a purely mechanical study of dry contact between the disc and pads is developed with a good prediction becomes a major stake for the industrialists while modeling the loading and the boundary conditions around the disc. The same computer code was used to visualize displacements, total deformations in the disc, shear stresses, Von Mises stresses and, the tools of contact pads. Also studied was the case of thermoelasticity while interpreting the various exits results during this simulation.

APA, Harvard, Vancouver, ISO, and other styles

32

Wan A. Hamid, W. L. H., L. Iannucci, and P. Robinson. "Finite-element modelling of NiTi shape-memory wires for morphing aerofoils." Aeronautical Journal 124, no. 1281 (June 24, 2020): 1740–60. http://dx.doi.org/10.1017/aer.2020.53.

Full text

Abstract:

AbstractThis paper presents the development and implementation of a user-defined material (UMAT) model for NiTi Shape-Memory Alloy (SMA) wires for use in LS-DYNA commercial explicit finite-element analysis software. The UMAT focusses on the Shape-Memory Effect (SME), which could be used for actuation of aerostructural components. The actuation of a fundamental structure consisting of an SMA wire connected in series with a linear spring was studied first. The SMA thermomechanical behaviour obtained from the finite-element simulation was compared with that obtained from the analytical solution in MATLAB. A further comparison is presented for an SMA-actuated cantilever beam, showing excellent agreement in terms of the SMA stress and strain as well as the tip deflection of the cantilever beam. A mesh sensitivity study on the SMA wire indicated that one beam element was adequate to accurately predict the SMA thermomechanical behaviour. An analysis of several key parameters showed that, to achieve a high recovery strain, the stiffness of the actuated structure should be minimised while the cross-sectional area of the SMA wire should be maximised. The actuation of an SMA wire under a constant stress/load was also analysed. The SMA material model was finally applied to the design of morphing aluminium and composite aerofoils consisting of corrugated sections, resulting in the prediction of reasonably large trailing-edge deflections (7.8–65.9 mm).

APA, Harvard, Vancouver, ISO, and other styles

33

Darcourt, C., J. M. Roelandt, M. Rachik, D. Deloison, and B. Journet. "Thermomechanical analysis applied to the laser beam welding simulation of aeronautical structures." Journal de Physique IV 120 (December 2004): 785–92. http://dx.doi.org/10.1051/jp4:2004120091.

Full text

Abstract:

The present work is being done in the framework of a national program about the lightening of aeronautical structures and describes a three-dimensional finite element simulation of the laser beam welding process. The targeted aeronautical structures are stiffened panels in aluminum alloys, which tend to replace riveted assemblies. Semi-coupled thermomechanical finite element analyses have been carried out to evaluate the magnitude and distribution of welding-induced residual stresses in order to take them into account for fatigue sizing. The finite element code MSC.Marc is used for the different calculations. Specific welding features have been added to the code through the implementation of a moving heat source or an elastoviscoplastic law. Experimental tests have been carried out in order to provide mechanical and thermal databases to the model. Monitored experimental welding have been made for comparisons with the simulation. In particular, results of thermocouple measurements have permitted to improve the thermal model.

APA, Harvard, Vancouver, ISO, and other styles

34

Bozic, Marko, Robert Fleischhauer, and Michael Kaliske. "Thermomechanical modeling of fiber reinforced material including interphasial properties and its application to epoxy/glass composites." Engineering Computations 33, no. 4 (June 13, 2016): 1259–81. http://dx.doi.org/10.1108/ec-07-2015-0188.

Full text

Abstract:

Purpose – The purpose of this paper is to investigate of interphasial effects, including temperature dependency, within fiber reinforced polymers on the overall composite behavior. Providing theoretical and numerical approaches in terms of a consistent thermomechanical finite element method framework are further goals of this research. Design/methodology/approach – Starting points for achieving the aims of this research are the partial differential equations describing the evolution of the displacements and temperature within a continuum mechanical setting. Based on the continuous formulation of a thermomechanical equilibrium, constitutive equations are derived, accounting for the modeling of fiber reinforced thermosets and thermoplastics, respectively. The numerical solutions of different initial boundary value problems are obtained by a consistent implementation of the proposed formulations into a finite element framework. Findings – The successful theoretical formulation and numerical modeling of the thermoinelastic matrix materials as well as the thermomechanical treatment of the composite interphase (IP) are demonstrated for an epoxy/glass system. The influence of the IP on the overall composite behavior is successfully investigated and concluded as a further aspect. Originality/value – A thermomechanical material model, suitable for finite thermoinelasticity of thermosets and thermoplastics is introduced and implemented into a novel kinematic framework in context of the inelastic deformation evolution. The gradually changing material properties between the matrix and the fiber of a composite are continuously formulated and numerically processed, in order to achieve an efficient and realistic approach to model fiber reinforced composites.

APA, Harvard, Vancouver, ISO, and other styles

35

Kawaragi, Yusuke, and Kazuo Okamura. "Application of Subloading Surface Model to Heat Treatment Simulation Based on Explicit Finite Element Method." Key Engineering Materials 725 (December 2016): 287–92. http://dx.doi.org/10.4028/www.scientific.net/kem.725.287.

Full text

Abstract:

The heat treatment simulation based on the explicit finite element method was developed. The subloading surface model considering the phase transformation was implemented in VUMAT of commercial FE code Abaqus/explicit. It is expected that the error of explicit analysis decrease in the stress integration, since the subloading surface model has an ability of pulling back stress state automatically to the yield surface in the plastic loading process. The formulation of subloading surface model in metallo-thermo-mechanics is presented, and the verification of the presented model is shown by the finite element quenching simulation. The deviation from the yield surface is less than that of the conventional explicit analysis, and the computation time is considerably less than that of the implicit analysis.

APA, Harvard, Vancouver, ISO, and other styles

36

Wei, Y., C. L. Chow, K. J. Lau, P. Vianco, and H. E. Fang. "Behavior of Lead-Free Solder Under Thermomechanical Loading." Journal of Electronic Packaging 126, no. 3 (September 1, 2004): 367–73. http://dx.doi.org/10.1115/1.1773197.

Full text

Abstract:

This paper presents an investigation of lead-free Sn-Ag base alloy, 95.5Sn-3.9Ag-0.6Cu, both experimentally and analytically. Experimentally, the deformation behavior of the material was measured for different temperatures (25°C and 1000°C) over a range of strain rates (10−5 to 10−3/s) under isothermal and thermomechanical conditions. Development of a unified viscoplastic constitutive model followed, taking into account the effects of the measured strain rate and temperature changes. The temperature rate effects are considered in the evolution equation of back stress. In order to include material degradation in the solder, the theory of damage mechanics is applied by introducing two damage variables in the viscoplastic constitutive model. Finally, the constitutive model is coded into a general-purpose finite element computer program (ABAQUS) through its user-defined material subroutine (UMAT). The damage-coupled finite element analysis (FEA) is then employed to monitor the condition of failure of a notched component. The predicted and measured maximum loads have been compared and found to be satisfactory. In addition, the calculated damage distribution contours enable the identification of potential failure site for failure analysis.

APA, Harvard, Vancouver, ISO, and other styles

37

Freßmann, Dirk, and Peter Wriggers. "A Micro- Thermomechanical coupled Finite-Element Model for the Simulation of Particulate Cellular Solids at Finite Strains." PAMM 3, no. 1 (December 2003): 274–75. http://dx.doi.org/10.1002/pamm.200310409.

Full text

APA, Harvard, Vancouver, ISO, and other styles

38

Zhao, Hui, Chong Yang, Dongxu Guo, Lu Wu, Jianjun Mao, Rongjian Pan, Jiantao Qin, and Baodong Shi. "Coupled Thermomechanical Responses of Zirconium Alloy System Claddings under Neutron Irradiation." Applied Sciences 11, no. 3 (February 1, 2021): 1308. http://dx.doi.org/10.3390/app11031308.

Full text

Abstract:

Zirconium (Zr) alloy is a promising fuel cladding material used widely in nuclear reactors. Usually, it is in service for a long time under the effects of neutron radiation with high temperature and high pressure, which results in thermomechanical coupling behavior during the service process. Focusing on the UO2/Zr fuel elements, the macroscopic thermomechanical coupling responses of pure Zr, Zr-Sn, and Zr-Nb binary system alloys, as well as Zr-Sn-Nb ternary system alloy as cladding materials, were studied under neutron irradiation. As a heat source, the thermal conductivity and thermal expansion coefficient models of the UO2 core were established, and an irradiation growth model of a pure Zr and Zr alloy multisystem was built. Based on the user material subroutine (UMAT) with ABAQUS, the current theoretical model was implemented into the finite element framework, and the consequent thermomechanical coupling behavior under irradiation was calculated. The distribution of temperature, the stress field of the fuel cladding, and their evolution over time were analyzed. It was found that the stress and displacement of the cladding were sensitive to alloying elements due to irradiated growth.

APA, Harvard, Vancouver, ISO, and other styles

39

Tolcha, Mesay Alemu, and Hirpa Gelgele Lemu. "Modeling Thermomechanical Stress with H13 Tool Steel Material Response for Rolling Die under Hot Milling." Metals 9, no. 5 (April 28, 2019): 495. http://dx.doi.org/10.3390/met9050495.

Full text

Abstract:

For the extreme pressure and temperature arising in the hot rolling process, thermomechanical (TM) models are used to predict the residual stresses on the surface of the die because a quantification of the TM stresses allows a prediction of the life span of the rolling die. As the accuracy and consistency of models developed in this area show a large variation due to the considered parameters, conditions, and assumptions, the capability of the developed models needs to be verified for a particular set of circumstances. In this study, new constitutive equations are proposed and a model consisting of five sub-models that computes temperature distribution, thermal stresses, mechanical stresses, and thermomechanical stress for the rolling die under continuous casting application has been developed and presented in this paper. The first sub-model describes the temperature distribution on the rolling die surface by accounting for the effects of different process parameters such as the initial temperature of the slab, reduction ratio, and the rolling speed, while the second and the third sub-models describe the thermal cyclic stress and the elasticity deformation of mechanical stress, respectively. Furthermore, the fourth sub-model describes the TM stress generation through inheriting numerical approaches, and the last sub-model is developed for the H13 tool material response at a high temperature. To verify the developed analytical models, a finite element simulation and the experimental data are considered. The analytical models are computed using Python, and the ABAQUS software has been used for the finite element simulations. The results show a good agreement with the finite element simulation and experimental data.

APA, Harvard, Vancouver, ISO, and other styles

40

Vandevelde, Bart, Eric Beyne, Kouchi (G Q. ). Zhang, Jo Caers, Dirk Vandepitte, and Martine Baelmans. "Parameterized Modeling of Thermomechanical Reliability for CSP Assemblies." Journal of Electronic Packaging 125, no. 4 (December 1, 2003): 498–505. http://dx.doi.org/10.1115/1.1604150.

Full text

Abstract:

Finite element modeling is widely used for estimating the solder joint reliability of electronic packages. In this study, the electronic package is a CSP mounted on a printed circuit board (PCB) using an area array of solder joints varying from 5×4 up to 7×7. An empirical model for estimating the reliability of CSP solder joints is derived by correlating the simulated strains to thermal cycling results for 20 different sample configurations. This empirical model translates the inelastic strains calculated by nonlinear three-dimensional (3D) finite element simulations into a reliability estimation (N50% or N100 ppm). By comparing with the results of reliability tests, it can be concluded that this model is accurate and consistent for analyzing the effect of solder joint geometry. Afterwards, parameter sensitivity analysis was conducted by integrating a design of experiment (DOE) analysis with the reliable solder fatigue prediction models, following the method of simulation-based optimization. Several parameters are analyzed: the PCB parameters (elastic modulus, coefficient of thermal expansion, thickness), the chip dimensions (area array configuration), and the parameters defining the solder joint geometry (substrate and chip pad diameter, solder volume). The first study analyzes how the solder joint geometry influences the CSP reliability. A second study is a tolerance analysis for six parameters. These parameters can have a tolerance (=accuracy) of their nominal value, and it is shown that these small tolerances can have a significant influence on the solder joint reliability.

APA, Harvard, Vancouver, ISO, and other styles

41

Ben Said, Lotfi, and Mondher Wali. "Accuracy of Variational Formulation to Model the Thermomechanical Problem and to Predict Failure in Metallic Materials." Mathematics 10, no. 19 (September 29, 2022): 3555. http://dx.doi.org/10.3390/math10193555.

Full text

Abstract:

The main purpose of this study is to develop a variational formulation for predicting structure behavior and accounting for damage mechanics in metallic materials. Mechanical and coupled thermomechanical models are used to predict failure in manufacturing processes. Ductile failure is accompanied by a significant amount of plastic deformation in metallic structural components. Finite element simulation of damage evolution in ductile solids is presented in this paper. Uncoupled models are implemented in a finite element model simulating deep drawing as well as cutting processes. Based on the Johnson–Cook model, the effect of deformation on the evolution of flow stress is described. The combined effect of strain, strain rate, and temperature on plasticity and damage behavior in cutting processes is considered. The accuracy of these models is verified when predicting ductile damage in forming and cutting processes.

APA, Harvard, Vancouver, ISO, and other styles

42

Shamim, Muhammad Babar, Marian Hörsting, and Stephan Wulfinghoff. "Variational Reduced-Order Modeling of Thermomechanical Shape Memory Alloy Based Cooperative Bistable Microactuators." Actuators 12, no. 1 (January 10, 2023): 36. http://dx.doi.org/10.3390/act12010036.

Full text

Abstract:

This article presents the formulation and application of a reduced-order thermomechanical finite strain shape memory alloy (SMA)-based microactuator model for switching devices under thermal loading by Joule heating. The formulation is cast in the generalized standard material framework with an extension for thermomechanics. The proper orthogonal decomposition (POD) is utilized for capturing a reduced basis from a precomputed finite element method (FEM) full-scale model. The modal coefficients are computed by optimization of the underlying incremental thermomechanical potential, and the weak form for the mechanical and thermal problem is formulated in reduced-order format. The reduced-order model (ROM) is compared with the FEM model, and the exemplary mean absolute percentage errors for the displacement and temperature are 0.973% and 0.089%, respectively, with a speedup factor of 9.56 for a single SMA-based actuator. The ROM presented is tested for single and cooperative beam-like actuators. Furthermore, cross-coupling effects and the bistability phenomenon of the microactuators are investigated.

APA, Harvard, Vancouver, ISO, and other styles

43

Chen, C., and R. Kovacevic. "Thermomechanical modelling and force analysis of friction stir welding by the finite element method." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 218, no. 5 (May 1, 2004): 509–19. http://dx.doi.org/10.1243/095440604323052292.

Full text

Abstract:

Friction stir welding (FSW) is a solid-state jointing technology, in which the butted plates are heated, plasticized and jointed locally by the plunged probe and shoulder moving along the joint line. The residual stresses due to the thermomechanical performance of the material and the constraint of the welded plates by the fixture are one of main concerns for this process. A prediction of the clamping force applied on the plates during FSW is expected to be helpful in controlling the residual stresses and weld quality. Furthermore, the prediction of the force history in FSW will be beneficial to understand the mechanics of the process and to provide valid models for controlling the process, especially in the case of robotic FSW. In this paper, a three-dimensional model based on a finite element method is proposed to study the thermal history and stress distribution in the weld and, subsequently, to compute mechanical forces in the longitudinal, lateral and vertical directions. The proposed model includes a coupled thermomechanical modelling. The parametric investigation of the effects of the tool rotational and longitudinal speed on the longitudinal, lateral and vertical forces is also conducted in order to compute the appropriate clamping force applied on the plates. Measurements by the load cells in the longitudinal, lateral and vertical directions are presented and reveal a reasonable agreement between the experimental results and the numerical calculations.

APA, Harvard, Vancouver, ISO, and other styles

44

Girrens, S. P., and F. W. Smith. "Constituent Diffusion in a Deformable Thermoelastic Solid." Journal of Applied Mechanics 54, no. 2 (June 1, 1987): 441–46. http://dx.doi.org/10.1115/1.3173034.

Full text

Abstract:

Solid mixtures containing initially uniform dilute concentrations of impurity elements may, upon the application of mechanical and thermal loading, develop regions of high impurity concentration that could result in local degradation of material properties. To address these degradation processes, a fully coupled thermomechanical-diffusion theory has been developed to describe the mass transport of mobile constituents driven by gradients in concentration, strain dilatation and temperature in a solid deformable parent material. A finite element code has been assembled to solve plane transient thermomechanical-diffusion problems. The theory presented and the resulting code have been successfully used to model internal hydrogen redistribution in β-phase Ti alloys induced by elastic strain gradients during bending.

APA, Harvard, Vancouver, ISO, and other styles

45

Christ, Daniel, and Stefanie Reese. "A finite element model for shape memory alloys considering thermomechanical couplings at large strains." International Journal of Solids and Structures 46, no. 20 (October 2009): 3694–709. http://dx.doi.org/10.1016/j.ijsolstr.2009.06.017.

Full text

APA, Harvard, Vancouver, ISO, and other styles

46

Liu, Peng Tao, Rui Ming Ren, Tian Cang Zhang, and Dong Ying Ju. "Numerical Simulation and Experiment of Linear Friction Welding Process of Ti6Al4V Alloy." Materials Science Forum 675-677 (February 2011): 925–28. http://dx.doi.org/10.4028/www.scientific.net/msf.675-677.925.

Full text

Abstract:

Using finite element analysis software of COSMAP, a three-dimensional elastic-plastic finite element model of linear friction welding (LFW) process of Ti6Al4V alloy was established. Based on metallo-thermo-mechanical theory relevant to describing the coupled fields of metallic structure, temperature and stress–strain, the temperature fields, phase transformation and stress fields during the LFW process were investigated in numerical simulation. Moreover, the validation experiment was carried out. The results showed that the simulation results of temperature，phase transformation and the residual stress were in good agreement with the experimental ones, which proved the numerical simulation to be reliable.

APA, Harvard, Vancouver, ISO, and other styles

47

Rajic, Milena, Milan Banic, Dragoljub Zivkovic, Misa Tomic, and Marko Mancic. "Construction optimization of hot water fire-tube boiler using thermomechanical finite element analysis." Thermal Science 22, Suppl. 5 (2018): 1511–23. http://dx.doi.org/10.2298/tsci18s5511r.

Full text

Abstract:

Exploitation experience of hot water boiler plants indicates relatively frequent and permanent breakdowns resulting from the accident state of various elements of the boiler. In addition to the damages caused by the corrosion processes and inadequate management of the plant, the phenomena of fatigue of boiler elements exposed to high pressures and temperatures can occur. Due to high pressure and temperature certain boiler elements are exposed to, high strain and stress of these elements can eventually lead to breakdowns. In this paper, a hot water fire tube boiler, produced by ?Minel-Kotlogradnja? Belgrade, type TE110V, installed within the plant ?Technical Faculties? at Faculty of Mechanical Engineering in Nis, Serbia, is analyzed. Thermomechanical stress-strain analysis is performed with loads typically occurring during operation. Finite element analysis is performed using ANSYS Workbench 17 Software package, while the CAD model is formed using SOLID WORKS 2015. The results were used to investigate and to give recommendations for the thickness of tube plate of the first reversing chamber based on determined functional dependence of equivalent stress in the tube plate from the thickness of the plate. The noted functional dependence was determined by Kriging response surface based on results of virtual numerical experiment with different thicknesses of the tube plate.

APA, Harvard, Vancouver, ISO, and other styles

48

Alshorbagy, A. E., S. S. Alieldin, M. Shaat, and F. F. Mahmoud. "Finite Element Analysis of the Deformation of Functionally Graded Plates under Thermomechanical Loads." Mathematical Problems in Engineering 2013 (2013): 1–13. http://dx.doi.org/10.1155/2013/569781.

Full text

Abstract:

The first-order shear deformation plate model, accounting for the exact neutral plane position, is exploited to investigate the uncoupled thermomechanical behavior of functionally graded (FG) plates. Functionally graded materials are mainly constructed to operate in high temperature environments. Also, FG plates are used in many applications (such as mechanical, electrical, and magnetic), where an amount of heat may be generated into the FG plate whenever other forms of energy (electrical, magnetic, etc.) are converted into thermal energy. Several simulations are performed to study the behavior of FG plates, subjected to thermomechanical loadings, and focus the attention on the effect of the heat source intensity. Most of the previous studies have considered the midplane neutral one, while the actual position of neutral plane for functionally graded plates is shifted and should be firstly determined. A comparative study is performed to illustrate the effect of considering the neutral plane position. The volume fraction of the two constituent materials of the FG plate is varied smoothly and continuously, as a continuous power function of the material position, along the thickness of the plate.

APA, Harvard, Vancouver, ISO, and other styles

49

Salifu, Smith, and Peter Apata Olubambi. "Thermomechanical properties prediction of wood-flour reinforced polymer composites using representative volume element (RVE)." MATEC Web of Conferences 370 (2022): 03002. http://dx.doi.org/10.1051/matecconf/202237003002.

Full text

Abstract:

The accurate prediction of the thermomechanical properties of newly developed polymer composites is important in the determination of their possible areas of application. In this study, a 3D model of representative volume element (RVE) with different wood flour weight ratios (5, 10, 15, 20, 25 and 30 %) was used to develop wood flour polymer composites. Micromechanical material modelling software (Digimat) was used in conjunction with finite element analysis software (Abaqus) to develop the polymer composites and to determine their thermomechanical properties (modulus of elasticity, Poisson’s ratio, thermal conductivity, density, and hardness). The hardness, tensile strength and modulus of elasticity increase with an increase in the wt.% of wood flour, while the Poisson ratio, thermal conductivity and density decrease with an increase in the wt.% of wood flour. Also, the predicted thermomechanical properties using the micromechanical material modelling software (RVE) follow the same trend as those found in the literature.

APA, Harvard, Vancouver, ISO, and other styles

50

Tang, Hong, and Cemal Basaran. "A Damage Mechanics-Based Fatigue Life Prediction Model for Solder Joints." Journal of Electronic Packaging 125, no. 1 (March 1, 2003): 120–25. http://dx.doi.org/10.1115/1.1536171.

Full text

Abstract:

A thermomechanical fatigue life prediction model based on the theory of damage mechanics is presented. The damage evolution, corresponding to the material degradation under cyclic thermomechanical loading, is quantified thermodynamic framework. The damage, as an internal state variable, is coupled with unified viscoplastic constitutive model to characterize the response of solder alloys. The damage-coupled viscoplastic model with kinematic and isotropic hardening is implemented in ABAQUS finite element package to simulate the cyclic softening behavior of solder joints. Several computational simulations of uniaxial monotonic tensile and cyclic shear tests are conducted to validate the model with experimental results. The behavior of an actual ball grid array (BGA) package under thermal fatigue loading is also simulated and compared with experimental results.

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'Metallo-thermomechanical finite element model'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles