Dissertations / Theses on the topic 'Welding numerical simulation'
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Cho, Min Hyun. "Numerical simulation of arc welding process and its application." Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1155741113.
Full textNekouie, Esfahani Mohammadreza. "Laser welding of dissimilar carbon steel to stainless steel 316L." Thesis, Loughborough University, 2015. https://dspace.lboro.ac.uk/2134/19760.
Full textEvdokimov, Anton [Verfasser]. "Numerical laser welding simulation of dissimilar Steel-Aluminum overlap joints / Anton Evdokimov." Düren : Shaker, 2020. http://d-nb.info/122416816X/34.
Full textWu, Tong Combescure Alain. "Experiment and numerical simulation of welding induced damage stainless steel 15-5PH /." Villeurbanne : Doc'INSA, 2008. http://docinsa.insa-lyon.fr/these/pont.php?id=wu.
Full textWu, Tong. "Experiment and numerical simulation of welding induced damage : stainless steel 15-5PH." Lyon, INSA, 2007. http://theses.insa-lyon.fr/publication/2007ISAL0091/these.pdf.
Full textL’objectif de cette étude est la prédiction du dommage et des contraintes résiduelles induites par des procédés haute température conduisant à une transformation de phase martensitique. On s’est intéressé plus premièrement à la modélisation du dommage induit par une histoire thermomécanique complexe, comme peuvent en produire les Zones Affectées Thermiquement de soudage. Nous proposons dans ce travail un modèle à deux échelles développé dans le cadre de la thermodynamique des processus irréversibles. Les équations de ce modèle couplent plasticité, endommagement, transformation de phase et plasticité de transformation. Nous avons réalisé de nombreux essais sur le 15-5PH en vue de l’identification des transformations de phase et des lois de comportement thermomécaniques. Les essais sur les éprouvettes entaillées ont été conçus pour valider les modèles d’endommagement ainsi que la localisation des déformations en utilisant la stéréo corrélation d’images. Les simulations numériques ont été effectuées avec le code CAST3M du CEA dans lequel nous avons implanté le méso modèle. Nous avons calculé l’état de contraintes résiduelles dans un disque de 15-5PH induites par un chauffage laser. En sus des contraintes, on peut suivre au cours du calcul les variables internes telles que l’endommagement ou les déformations anélastiques. Les simulations montrent que la plasticité de transformation modifie le niveau des contraintes résiduelles et peut ne pas être négligeable. Quand à l’endommagement, celui-ci fait décroître les valeurs maximales de contrainte résiduelles jusqu’à huit pourcent dans les zones les plus sollicitées
Kiranmayi, Abburi Venkata. "Characterising high energy beam welding in structural steels with numerical simulation and validation." Thesis, University of Bristol, 2015. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.683553.
Full textLindgren, Lars-Erik. "Deformations and stresses in butt-welding of plates : numerical simulation and experimental verification." Doctoral thesis, Luleå tekniska universitet, Material- och solidmekanik, 1985. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-26528.
Full textGodkänd; 1985; 20070424 (ysko)
Zhang, Kaiwen. "IN-SITU MEASUREMENT AND NUMERICAL SIMULATION OF LINEAR FRICTION WELDING OF Ti-6Al-4V." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1578051567375844.
Full textRobe, Hugo. "Apports à la compréhension du soudage FSW hétérogène d’alliages d’aluminium par une approche expérimentale et numérique." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSEE005/document.
Full textThe lightweight structures optimisation is one of the main topics in transportation industry. It can be achieved by optimisation of materials as well as induced assembly process. As a solid-state process, Friction Stir Welding (FSW) allows to produce dissimilar materials joining while avoiding fusion defects. This work focused on the dissimilar welding of aluminium alloys from 2xxx (Al-Cu-Mg-Ag) and 7xxx (Al-Zn-Mg) series in an industrial context. Joints characterizations were conducted at multiple scales to understand parameters impact on material flow, joint morphology, and performances. They have shown large heterogeneities in the microstructure as well as the global and local mechanical behaviour. Whatever the welding parameters used, good mechanical performance has been reached. A specific softened zone has been detected in the 7xxx alloy’s HAZ which caused fracture during transverse tensile test. Significant metallurgical evolution induced by thermal cycles mainly explains these phenomena.On the other hand, simulation works were also conducted to simulate the welding process in similar material configuration. The finite elements model integrates, for the first time, the real and complex tool design (thread, flats…). Complex geometry can be used by coupling with a specific moving mesh technique. This numerical development completely overcomes the consequent mesh distortion often encountered in FSW simulation. The current model presents good sensitivity and robustness for several welding conditions and materials. It also demonstrates an excellent correlation between experimental and numerical thermal fields while revealing the predictive aspect of the model
Ehlen, Georg [Verfasser]. "Transient Numerical Simulation of Complex Convection Effects during Solidification in Casting and Welding / Georg Ehlen." Aachen : Shaker, 2004. http://d-nb.info/1170537685/34.
Full textKaars, Jonny, Peter Mayr, and Kurt Koppe. "Determining Material Data for Welding Simulation of Presshardened Steel." MDPI AG, 2018. https://monarch.qucosa.de/id/qucosa%3A31829.
Full textPavlyk, Vitaliy [Verfasser]. "Modelling and Direct Numerical Simulation of Dendritic Structures under Solidification Conditions during Fusion Welding / Vitaliy Pavlyk." Aachen : Shaker, 2004. http://d-nb.info/1170545319/34.
Full textNoori, Rahim Abadi Seyyed Mohammad Ali. "Investigation of Melt Pool Thermo-hydrodynamic Behaviour inLaser Beam Welding ofTi-6Al-4V through Numerical Simulation." Licentiate thesis, Högskolan Väst, Avdelningen för svetsteknologi (SV), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:hv:diva-17410.
Full textLaser är en effektiv och allmänt använd värmekälla vid svetsning och additiv tillverkning. Den har några viktiga fördelar jämfört med andra konventionella värmekällor såsom elektronstråle och elektrisk ljusbåge, nämligen: den kan ofta användas till komplicerade svetsgeometrier, och den kan producera stora komponenter. Lasersvetsning involverar olika sammansatta fysikaliska fenomen såsom värmeöverföring, metallsmältning, flöde, stelning, ytdeformation, avdunstning och i vissa fall förångning. Syftet med mitt forskningsarbete är tvåfaldigt: att få en djupare processförståelse och att förbättra modellens tillförlitlighet. Fördjupad processförståelse eftersträvades för att förstå hur formen på laserstrålen påverkar svetssmältan. För att uppnå förbättrad modellsäkerhet behövs experimentella data av hög kvalitet som representerar processen. Således utfördes 3D-validering av smältgeometrin medan det vanligtvis var 2D i tidigare forskningsarbeten. Dessutom har en ny modell för laserabsorption föreslagits. I forskningen har numerisk strömningssimulering (Computational Fluid Dynamics) använts för att simulera processen och en numerisk lösare, som kan spåra deformationen av den rörliga smälta ytan, är utveckladi programvaran OpenFOAM. Beträffande laserstrålens utbredning visar resultaten att svetssmältans storlek och även svetssmältansflöde modifieras genom att laserstråleformen förlängs. Medan den förra är känd från tidigare experimentella studier upptäcktes den senare inte före denna studie eftersomdet icke-transparenta mediet hindrar optisk observation. Nya (in-process) kvantitativa mätningar utförda av en projektpartner har använts för att testa modellerna. Svagheter i den tidigare absorptionsmodellen framhävdes, liksom begränsningarna i den föreslagna modellen. Slutligen visade resultaten att den föreslagna modellen där laserabsorptionen är en funktion av lokala ytförhållanden ledde till en bättre overensstämmelse med mätningar jämfört med den tidigare modellen med konstant laserabsorbtion. Den maximala avvikelsen jämfört med experimentell mätning, som observerades med avseende på smältbassängsdjupet, kunde reduceras till cirka 10%.
Till licentiatuppsats hör 2 inskickade artiklar, som inte visas nu.
NAKAMURA, Takashi, 達也 長谷川, Tatsuya HASEGAWA, 雄一郎 高井, Yuichiro TAKAI, 晋太郎 土井, Shintaro DOI, 隆. 中村, 知宏 前田, and Tomohiro MAEDA. "レーザによる熱可塑性プラスチックのラップ接合 (第3報, 数値シミュレーションによる接合条件の検討)." 日本機械学会, 2002. http://hdl.handle.net/2237/9093.
Full textAhn, Joseph. "Experimental characterisation and numerical simulation of fibre laser welding of AA 2024-T3 and Ti-6Al-4V." Thesis, Imperial College London, 2016. http://hdl.handle.net/10044/1/53827.
Full textVaněk, Mojmír. "Predikce deformací svarových spojů pomocí počítačové simulace." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2012. http://www.nusl.cz/ntk/nusl-230286.
Full textHanna, Farah. "A thermo-metallurgical-mechanical model for the numerical simulation of multipass GTA welding of martensitic X10CrMoVNb9-1 steel." Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066416/document.
Full textDue to its microstructural stability, the martensitic steel 'X10CrMoVNb9-1 is considered a candidate for several future high temperatures reactor components. These thick components (200 mm) are assembled by GTA multi-pass welding. This welding process generates complex thermal and thermomechanical cycles in the Heat Affected Zone (HAZ). This thesis is following that of G.-M. Roux. This work of 6 years aims to predict the microstructural state after welding in the HAZ. A first version of a Thermo-Metallurgical-Mechanical model (TMM) has been developed and validated in terms of residual stresses on single-pass welding simple tests. In this thesis a new version of the TMM model is proposed to improve the forecasts in terms of the microstructural state and residual stresses post welding in the HAZ. The main improvements of this model TMM its capabilities to take into account the successive heating and cooling cycles, characterizing the multi-pass welding process. This thesis is based on a detailed modeling approach for phase transformations, namely modeling the transformation base material - austenite during anisothermal complex loadings, modeling transformation austenite - martensite and finally the martensite tempering modeling. Not to mention the characterization of the mechanical behavior of each phase and the study of multiphase behavior. Numerical simulation with the finite element code Cast3M of several welding processes was used to compare models with experimental results
Karki, Utsab. "Experimental and Numerical Study of High-Speed Friction Stir Spot Welding of Advanced High-Strength Steel." BYU ScholarsArchive, 2015. https://scholarsarchive.byu.edu/etd/5521.
Full textLocatelli, Fabio Renck. "Modelagem do campo de temperaturas e distorções de uma junta do tipo T soldada pelo processo GMAW." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2014. http://hdl.handle.net/10183/103840.
Full textThe high heat flow involved in the component’s welding process favors the appearance of residual stress, which alleviation provides the appearance of distortions. Once these distortions can impair the use of the components, become relevant searches about the parameters, measurement and prediction of distortions. This work aims to analyze the distortions in GMAW welding of a T-type joint, through thermo-structural study in a numerical model by finite element method with experimental validation. For this, the work was divided in two sequential stages, the first aimed to the numerical model’s validation and the second to the development of numerical cases to analysis. The numerical model uses three-dimensional finite elements for obtainment the temperature field and distortions. For the application of heat flow to the part was used the Goldak’s equation as a model of heat input in transient thermal analysis. The temperature dependence in the variation of physical and mechanical properties of the materials was considered. The experimental part of the first stage allowed to define two welding speeds while keeping the same process energy, originating two sets of parameters called principal and alternative. In the second stage, eight cases were analyzed, defined by the combination of three variables: speed variation, sequence of welding and cooling time between fillets. The transient temperature field is checked by measuring temperatures in eight points, while the distortion field is checked using a coordinate measuring system. Among all cases analyzed, the lowest distortion was observed in case 6 (fastest speed, "going-back" sequence and cooling interval) in which the maximum distortion was 4.31 mm, while the largest distortion was presented by the case 4 (slower speed, "go-go" sequence and cooling interval) with maximum distortion of 6.41 mm.
Awang, Draup Awang Jefri. "Numerical simulation of the structural response of friction stir welded aluminium 2139-T8 alloy subjected to complex loading configurations." Thesis, University of Manchester, 2017. https://www.research.manchester.ac.uk/portal/en/theses/numerical-simulation-of-the-structural-response-of-friction-stir-welded-aluminium-2139t8-alloy-subjected-to-complex-loading-configurations(a840bd28-102d-4c15-be6c-b4e72631e875).html.
Full textZain-ul-abdein, Muhammad. "Experimental investigation and numerical simulation of laser beam welding induced residual stressed and distorsions in AA 6056-T4 sheets for aeronautic application." Lyon, INSA, 2009. http://theses.insa-lyon.fr/publication/2009ISAL0069/these.pdf.
Full textCe travail se concentre sur les mesures expérimentales et les simulations numériques des contraintes résiduelles et des distorsions induites par le soudage laser utilisant les conditions aux limites mécaniques et thermiques, appliquées dans le milieu industriel sur des plaques minces d’un alliage d'aluminium AA 6056-T4. Plusieurs expériences de petites échelles ont été réalisées avec différents instruments, comme des thermocouples et des capteurs LVDT qui ont été utilisés pour enregistrer, respectivement, les températures et les déplacements pendant le soudage. La caméra infrarouge a été aussi utilisée pour qualifier l’évolution de la température de bain fondu en fonction du temps. Les mesures de déplacements dans le plan et hors-plan ont été obtenues par stéréo-corrélation d’images. Une micrographie a été réalisée pour mesurer les dimensions de la zone de fusion. La base de données ainsi préparée a servi de point de référence pour la validation des résultats de simulation numérique. La caractérisation thermomécanique du 6056-T4 est également effectuée pour identifier les propriétés des matériaux à utiliser lors de la simulation numérique. Les simulations par éléments finis sont effectuées avec le logiciel commercial Abaqus et les modèles de source de chaleur volumétrique avec distribution Gaussienne du flux sont programmés en Fortran. Les conditions aux limites thermiques et mécaniques utilisées dans l’industrie sont intégrées aux modèles. Les analyses thermiques sont effectuées en premier pour atteindre la géométrie de zone de fusion et les champs de température souhaitées. Les analyses mécaniques sont effectuées ensuite pour prédire la déformation et l’état de contraintes résiduelles. La loi de comportement du matériau est considérée élasto-plastique / élasto-viscoplastique avec écrouissage isotrope (modèle de plasticité de von Mises). Les analyses comparatives entre les résultats expérimentaux et les simulations présentent une bonne concordance des valeurs. Enfin, les états de contraintes et déformations résiduelles sont évaluées par calcul
Dinh, Trong Tuan. "Modèles hyper-réduits pour la simulation simplifiée du soudage en substitut de calcul hors d’atteinte." Thesis, Paris Sciences et Lettres (ComUE), 2018. http://www.theses.fr/2018PSLEM023/document.
Full textMulti-pass welding is used to recharge pipes with local sub-thickness. Numerical simulation facilitates the selection of many welding parameters. Reducing the order of models speeds up these choices. In this work, we were interested in cases where it is difficult to carry out the entire welding simulation due to time constraints or lack of calculation means. These computations are called out of reach simulations. However, the missing forecasts do not allow the implementation of a orthogonal decomposition method to extract a reduced basis of empirical modes from the data produced by numerical simulations. To overcome this difficulty, we propose either a directional model well adapted to welding, or a step of extrapolation of the simulation data by spatial shift of the already calculated forecasts. These two approaches are complementary to the hyper-reduction method, in which the balance equations are restricted to a reduced mesh size. These methods allow to start a numerical simulation of welding with a finite element model, then to continue this simulation with a hyper-reduced model. This avoids the need for numerous preliminary parametric studies and allows simulations that are out of reach. This manuscript ends with a chapter dealing with the case of reloading a tube, for which EDF has carried out an instrumented test
Gastebois, Sabrina. "Simulation numérique du soudage FSW à l'aide d'une formulation ALE." Thesis, Paris, ENMP, 2015. http://www.theses.fr/2015ENMP0040/document.
Full textSince the invention of Friction Stir Welding (FSW) in 1991 by The Welding Institute (TWI), aeronautics industry has been investigating the possibility to use this process instead of riveting with the objective to lighten its structures and more particularly the aircrafts structure panels. Aircraft panels are often straightened with stringers and profiles which are joined to the outer skin. The qualification of FSW process in aeronautics requires producing very high quality joints with the longevity of tools, which requires fine tuning of process parameters such as the geometry of the welding tool (shoulder and pin dimensions, threads on pin and shoulder) and the advancing and rotating speeds. The aim of this work is to support the design of the process by numerical simulation. It has three parts: (1) developing an efficient and accurate Arbitrary Lagrangian or Eulerian (ALE) formulation within the parallel version of Forge® software, (2) modelling the FSW process and (3) calibrating the F.E. model and validating simulation results thanks to FSW experiments on lap joints.This work is based on the parallel ALE formulation developed in Forge® to model the different possible defects taking place in FSW (flashes and worm holes). The transport algorithm of continuous fields, required by the Eulerian frame, is enhanced to take the special characteristics of the FSW's flow into account (nodes located in input plan or flashes or in contact with the tool). A new time integration scheme based on cylindrical coordinates, which are best suited for this process, is introduced. Finally, the pin and shoulder threads are modelled by introducing a new friction law at the tool / material interface.This general and parallel ALE formulation is robust enough to model the FSW process. Thermomechanical results obtained are in agreement with previous results validated by experiences. And the numerical tool demonstrated its ability to model flashes formation and losses of contact behind the pin. Finally industrial welding lap joints configuration was studied. Experimental tests were conducted with several process parameters and type of lap joint. And measure of torque and forces in tool, and temperature in tool and sheet metal allowed to calibrate model parameters (friction, behavior law, thermal coefficients) and to validate FE results
Richter, Tomáš. "Svařování rotorových materiálů." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2012. http://www.nusl.cz/ntk/nusl-230289.
Full textVaněk, Mojmír. "Vývoj modelů chování Al slitin pro aplikace v numerických simulacích svařování a tepelného zpracování." Doctoral thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2017. http://www.nusl.cz/ntk/nusl-364598.
Full textGraf, Marcel, Sebastian Härtel, and André Hälsig. "Numerische Auslegung des Mehrlagenschweißens als additives Fertigungsverfahren." Universitätsbibliothek Chemnitz, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-225946.
Full textTirand, Guillaume. "Etude des conditions de soudage laser d'alliages à base aluminium par voie expérimentale et à l'aide d'une simulation numérique." Thesis, Bordeaux 1, 2012. http://www.theses.fr/2012BOR14482/document.
Full textThe development of laser welding in various branches of industry particularly in the aeronautics during the last decade, required many studies still insufficient in number to understand and control the conditions of laser welding concerning laser / material interaction,as well as thermal transfers or metallurgical aspects. The approach followed in this study consists (1) to bring to light experimentally the problem of laser welding of aluminium based alloy, that is the coupling of the effects between the various welding parameters, (2) to describe the thermal history of an operation of laser welding from a modelling and from a numerical simulation and (3) to exploit the knowledge of the thermal evolution of an assembly all along welding operation to optimize the mechanical performance of the assembly in term of static resistance, resistance to hot cracking, fatigue and corrosion resistance. The deficit of performance for example in term of tensile resistance is mainly related to too low speeds of cooling during welding compared with quenching. It justifies the efficiency of a post welding solution heat treatment before a precipitation hardening treatment
Timesli, Abdelaziz. "Simulation du soudage par friction et malaxage à l'aide de méthodes sans maillage." Thesis, Université de Lorraine, 2013. http://www.theses.fr/2013LORR0111/document.
Full textFriction stir welding is a recent process that has been developed by the British Welding Institute TWI "The Welding Institute" since 1990s. This process, generally used in aerospace, does not need additional material and allows mainly joining plates of aluminum alloys which are difficult to weld by the classical welding processes. It consists in mixing the base material using a tool comprising a pin and a shoulder which heats the plates to be welded by friction. The modeling of this process is very complex since it involves the coupling between mechanical, thermal and metallurgical phenomena. The mixing in welding process FSW is difficult to simulate using finite element method in lagrangian framework since the area near the welding tool is submitted to large deformations. So remeshing procedure is often required. However, remeshing can be very expensive and difficult to perform for three-dimensional problems. Moreover, after remeshing step, it is necessary to interpolate the fields (velocities, constraints ...) corresponding to the current solution, which may lead to additional errors in the calculation (called numerical diffusion). We propose in this work models based on meshless methods called "Smoothed Particle Hydrodynamics SPH" and Moving Least Square method for the simulation of this welding process. These models are formulated in lagrangian framework and use the strong form of partial differential equations. The first model based on SPH considers the welding zone as a weakly compressible non-newtonian fluid and whose viscosity depends on the temperature. This model is proposed for the numerical simulation of thermo-mechanical behavior of a welded material by FSW process. The second model is a first order implicit iterative algorithm proposed to simulate material mixing in the case a visco-plastic behavior using the MLS method and the collocation technique. The third model is a high order implicit algorithm based on the coupling of MLS method and Asymptotic Numerical Method (ANM). This algorithm allows reducing the computation time by comparison with the first order implicit iterative algorithm. The validation of these three proposed models was done by the industrial code Fluent
Mackwood, Andrew. "Numerical simulations of thermal processes and welding." Thesis, University of Essex, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.272572.
Full textBezerra, Alexandre Campos. "Simulação numérica da soldagem com aplicação à caracterização do comportamento dinâmico de estruturas soldadas." Universidade Federal de Uberlândia, 2006. https://repositorio.ufu.br/handle/123456789/14774.
Full textNowadays, welded structures are widely employed in engineering design. Generally, these structures have internal stresses (residual stresses) generated by the thermal cycle to which these parts are submitted during welding process. In many cases, these stresses are not minimized by means of thermal treatment. Thus, one must take into account the residual stresses in the design of welded components. However, computation of residual stress field is not an easy task and, besides, it is important to evaluate the quality of welded components. Therefore, by using the advantage of the fact that the stress state influences the mechanical behavior of components and structures (stress stiffening effect), it was proposed to evaluate the viability of a methodology to control the quality of welded components, by means of dynamic responses. This way, it was verified experimentally the sensitivity of vibrating natural frequencies to welding residual stress in different structures. It was confirmed that thin structures are more sensitive to the stress stiffening effect. To evaluate this effect numerically, a procedure to simulate welding was validated by using experimental data from literature. This procedure was used to obtain the residual stress field. This stress field is included in a modal analysis to verify the modifications of natural frequencies. Numerical results were compared to experimental results obtained here, showing a good agreement. It was also proposed to use the electromechanic impedance technique to evaluate the stress stiffening effect. An analysis of the results shows the possibility of use the stress stiffening effect to implement a methodology for quality control of welded components.
Atualmente, estruturas soldadas encontram-se amplamente aplicadas em projetos de engenharia. Normalmente, estas estruturas apresentam tensões internas (residuais) devidas ao ciclo térmico ao qual são submetidas durante a soldagem. Em muitos casos, estas tensões não são minimizadas por meio de tratamento térmico, havendo assim a necessidade de inclusão destas em projeto. Entretanto, a determinação do campo de tensões residuais não é tarefa fácil e, no caso de uma produção em série, é importante avaliar a qualidade do componente confeccionado. Sendo assim, aproveitando o bem conhecido fato de o comportamento mecânico de componentes e estruturas sofrer influência do estado de tensão (enrijecimento por tensão), propõe-se avaliar a viabilidade de uma metodologia de controle de qualidade de peças soldadas por meio de respostas dinâmicas. Desta forma foi verificada experimentalmente a sensibilidade das freqüências naturais de vibração ao estado de tensões residuais de soldagem em diferentes estruturas. Confirmou-se que estruturas esbeltas são mais sensíveis ao enrijecimento por tensões residuais de soldagem. Com a finalidade de avaliar este efeito numericamente, um procedimento para simulação da soldagem foi validado utilizando-se dados experimentais da literatura. Na seqüência, utilizou-se tal procedimento para, após a determinação das tensões residuais de soldagem, realizar uma análise modal e avaliar as alterações nas freqüências naturais de vibração (e conseqüentemente o efeito do enrijecimento por tensão). Os resultados numéricos foram confrontados com os resultados experimentais obtidos neste trabalho, apresentando uma boa concordância. Finalizando o trabalho, propõe-se utilizar a técnica da impedância eletromecânica para avaliar o enrijecimento por tensão. Uma avaliação dos resultados mostra ser possível utilizar o enrijecimento por tensão para implementar uma metodologia para controle de qualidade de componentes soldados.
Doutor em Engenharia Mecânica
Nguyen, Minh Chien. "Modélisation et simulation multiphysique du bain de fusion en soudage à l'arc TIG." Thesis, Aix-Marseille, 2015. http://www.theses.fr/2015AIXM4749/document.
Full textIn this work, we develop a 3D physical and numerical model of the GTA (gas tungsten arc) welding process in order to predict, for given welding parameters, useful quantities for the designer of welded assembly.The model is developed in the Cast3M finite element software and takes into account the main physical phenomena acting in the workpiece and particularly in the weld pool, subject to source terms modeling the arc part of the welding process. A steady solution of this model is thought for and involves the coupling of the nonlinear thermohydaulics and electromagnetic equations together with the displacement of the deformable free surface of the weld pool.A first step in the development consisted in modeling the electromagnetic phenomena with two different numerical methods, in comparing the numerical results obtained with those of the literature. Then, in order to assess the predictive capability of the model, simulations of various welding configurations are performed : variation in the chemical composition of the material, of the welding speed, of the prescribed arc pressure and of the welding positions, which is a focus of this work, are studied. A good agreement is obtained between the results of our model and other experimental and numerical results of the literature. Eventually, a model accounting for metal filling is proposed and its results are discussed. Thus, our complete model can be seen as a solid foundation towards future totally-coupled 3D welding models including the arc and it will be included in the WPROCESS software dedicated to the numerical simulation of welding
Le, Gloannec Brendan. "Modifications microstructurales sous sollicitations thermomécaniques sévères : application au soudage par résistance des gaines de combustibles en aciers ODS." Thesis, Bordeaux, 2016. http://www.theses.fr/2016BORD0367/document.
Full textOxide dispersion strengthened (ODS) steels are considered as candidate materials for thedevelopment of fuel cladding for sodium-cooled fast reactors (SFR). Resistance upset welding of thecladding is studied in this work. The aim is to determine and to understand the process effects on themicrostructure of ODS steels with 9% and 14% of chromium at the scales of the grains and thenanometric oxides. An approach coupling microstructural characterization of welds, numericalsimulation and physical simulation of the process, using a thermomechanical simulator Gleeble 3500,is proposed. Resistance welding locally imposes severe thermomechanical conditions in terms of strain,strain rate and temperature. Refinement of the microstructure is noted and correspond to a dynamicrecrystallization mechanism (14 % Cr steel) or the combination of dynamic recrystallization and phasetransformations (9 % Cr steel). The conditions of occurrence of dynamic recrystallization are studied.The possibility of a transition between continuous and discontinuous dynamic recrystallization is shownfor the 14 % Cr steel according to the loading conditions. Such severe thermomechanical conditionsinduce an increase in the size of nanoscale oxides associated with a decrease of their volume fraction
Beaurin, Gauthier. "SIMULATION ET ÉTUDE EXPÉRIMENTALE DES CONTRAINTES RÉSIDUELLES DANS LES DÉPÔTS DURS NOREM DES MATÉRIELS DE ROBINETTERIE." Phd thesis, INSA de Lyon, 2012. http://tel.archives-ouvertes.fr/tel-00759226.
Full textGuedoiri, Ammar. "Contribution à la modélisation et à la simulation numérique du soudage par friction et malaxage." Phd thesis, Paris, ENSAM, 2012. http://pastel.archives-ouvertes.fr/pastel-00842393.
Full textSeang, Chansopheak. "Evaluation numérique des contraintes résiduelles appliquée à l'acier DP600 soudé par laser de haute puissance Nd : YAG." Phd thesis, INSA de Rennes, 2013. http://tel.archives-ouvertes.fr/tel-00875121.
Full textSaadlaoui, Yassine. "Simulation numérique des procédés thermomécaniques dans une approche couplant les écoulements du fluide avec les déformations du solide : application au soudage laser et à la fusion d'un lit de poudre." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSES005.
Full textIn the current study, numerical methods are developed to simulate the laser welding and the melting of a powder bed while taking into account their complexity. These methods are based on a new strategy of fluid/solid coupling. They allow to simulate the formation of the melted zone by taking into account the fluid flows through the two effects of the surface tension ("curvature effect" and "Marangoni effect") and the buoyancy. An ALE approach is used to follow the evolution of the free surface. The interaction between the fluid flows in the molten pool and the deformations in the solid part is ensured by imposing the velocities of the solid nodes during the fluid computation. Several analytical and numerical tests are used to validate the formulation of the fluid problem and the new strategy of fluid/solid coupling. The results confirm the efficiency and the robustness of the numerical methods developed.As first application, a thermal-fluid-mechanical simulation of laser welding is carried out. The results obtained show a good correlation with the literature results. The second application consists of simulating the melting of a powder bed. It allows to take into account the shrinkage of the powder layer after melting, and the change of the thermalphysical properties depending on the material state (powder or compact).Although the study consisted mainly in developing numerical methods, it also includes an experimental part. Specific set-up has been done using different instrumentation tools. These tools allow to better understand the physical phenomena involved during the two processes. In a second step, a database (morphology of molten pool, temperature and residual stresses) on welded parts is constituted. This database will allow in a subsequent work to carry out a global validation process of the proposed numerical methods
Friedrich, Nils [Verfasser]. "Approach to consider welding residual stresses in fatigue analysis using numerical simulations / Nils Friedrich." Hamburg : Universitätsbibliothek der Technischen Universität Hamburg-Harburg, 2020. http://d-nb.info/1219963631/34.
Full textSarre, Benjamin. "Influence du soudage laser Nd˸YAG sur les propriétés métallurgiques et mécaniques de l'alliage de titane TA6V." Thesis, Troyes, 2018. http://www.theses.fr/2018TROY0019.
Full textWelding operation consists of assembling two or more pieces to ensure the continuity of a structure. The resulting assembly may withstand mechanical loads. However, the welding operation modifies the state of materials. In other words, the metallurgical and mechanical behaviour of the latter is deeply affected. This work aims to better understand the influence of welding on the metallurgical and mechanical behavior of the Ti-6Al-4V titanium alloy. Comprehensive metallurgical analyses of the welded joint are carried out and reveal a sharp and strong microstructure gradient between the fusion zone and the base metal. Several residual stress fields are quantified by X-ray diffraction analyzes. Those residual stress fields are then compared with finite element simulations of the welding of a Ti-6Al-4V titanium alloy. The simulation are based on a weakly coupled model that accounts for temperature, stresses and phase transformations. The failure behaviour of the welded joint is studied. An overmatch was highlighted with mechanical tests. The fracture finally occurs in the base metal despite the presence of defects in the fusion zone. A Gurson-Tvergaard-Needleman approach is carried on. The mechanical parameters are quantified from mechanical tests on homogeneous samples of base metal and of a representative microstructure of the welded joint, which has been obtained from heat treatments. The model are in good agreement with mechanical tests
Dohnal, Ivo. "Numerická simulace svařování lopatky a rotoru turbíny." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2010. http://www.nusl.cz/ntk/nusl-229216.
Full textSilva, Miguel Castro. "Numerical simulation of strains and stresses in welding." Master's thesis, 2020. http://hdl.handle.net/10773/31335.
Full textA soldadura é dos métodos mais conhecidos na indústria para unir uma grande variedade de materiais. Este processo cria inevitavelmente tensões e deformações nos componentes devido à alta intensidade de energia libertada pela fonte de calor. Nos dias que correm torna-se quase obrigatório quantificar estas alterações nas peças que passam pelo processo de soldadura. Só assim é possível cumprir rigorosos parâmetros de qualidade, garantindo que a peça cumpre a função atribuída. É muito comum recorrer a métodos experimentais para fazer esta análise. No entanto, o uso de métodos computacionais em simulação de processos de soldadura tem crescido significativamente. A simulação numérica, baseada no Método de Elementos Finitos, surge para facilitar aos engenheiros a prevenção e análise de fenómenos complexos. No presente trabalho foram desenvolvidos dois modelos de simulação numérica do processo de soldadura através de laser em chapas de Dual-Phase 600. Foram testados 2 tipos de juntas: topo a topo e em T. As deformações e tensões causadas pelo processo foram quantificadas com recurso ao software Simufact.
Mestrado em Engenharia Mecânica
Chen, Jin-Syong, and 陳錦雄. "Experimental and Numerical Simulation ofMultilayer Welding on Stern Tube." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/53283900006099999161.
Full text國立臺灣海洋大學
輪機工程學系
103
Ship propulsion shaft system will vary with the various needs change and causes torsional, compressive and bending stress. Also, the waterway restrictions due to environmental factors, ship has sailing crisis when re- floats as lightheadness causing the stern section fracture. Nowadays the shipyard applies gas metal arc welding method technology, with more eco- nomic effectiveness. The gas metal arc welding method has the advantages of rapid production but the heat leads large welding deformation and stress concentration. As the important part of the ship, the butt welding process must have strict control to guarantee the strength and rigidity. In this thesis, we adopt the finite element analysis to model and predict weld bead temperature, thermal stress and strain and structure deformation. NotonlytheFiniteelementMethodsfindoutthetemperatureproblemsaris- ing from welding, but also avoid welding deformation after welding phe- nomenon. For the construction of various factors on the functioning reg- ularity based on the weld temperature, the stress and strain fields will be fully understand the operation of the welding process and comparison with the experimental model. This model will to maintain accuracy, but also has a great, much computationally efficient, centralized heat welding charac- teristics reflect movement for segmenting process for moving heat source, but the member is actually relatively large structures for the calculation and computationonalargescale,andalsomoredifficulttoachieveconvergence to solve. We use segmented moving heat source model will comparable to the heat source model and thus also the efficiency and accuracy can be achieved consistency. This thesis adopts the inherent-strain method to predict the welding de- formationwithexperimentalmodel. Numericalsimulationofweldinginthe field of general simple welded structure with analytical calculation formula and some experiences formula, welding numerical analogy with a system, flexible features produce the results need to be physical analog modeling verification before a reference to the production line. It will be applied to virtually component production. Keywords: ship propulsion shafting, finite element method, welding deformation, segmented moving heat source model.
ITOH, Y., and M. HIROHATA. "NUMERICAL SIMULATION OF WELDING DEFORMATION AND RESIDUAL STRESS BY FEM WITH SHELL ELEMENTS." 2013. http://hdl.handle.net/2237/18866.
Full text"Numerical simulation of welding with application on the dynamic behavior characterization of welded structures." Tese, Biblioteca Digital da Universidade Federal de Uberlândia, 2006. http://www.bdtd.ufu.br//tde_busca/arquivo.php?codArquivo=1050.
Full textHo, Hung-Wei, and 何宏瑋. "Numerical Simulation of Rollover Test on Complete Vehicle Considering the Effects of Welding Joints." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/96799827940227069042.
Full text大葉大學
車輛工程學系碩士班
96
Buses are the high loading capacity transportation on the road. When a major accident happened, the passengers would be serious injury. When a rollover accident of a bus happened, the damage often occurred in the weld zone. For passengers’ safety, the design of superstructure of the bus should consider the weld zone which would affect the strength of a bus rollover accident. From the previous numerical analysis, the weld zone often idealistic assemble at an concurrent way. But those analysis did not account of the effects of welding. This paper adopted nonlinear software LS-DYNA to study the rollover strength of bus. At first, this paper added the failure criteria of both fillet welding and butt welding to the extrusion simulation analysis of a bus frame structure. Then compared the difference with the result of idealistic assemble at concurrent way. The result densely match with the previous experiment which considered welding. The elongation which the weld zone of roof structure failure is only 7.4% different from the previous experiment. The elongation which the weld zone of pillar structure failure is only 3.7% different from the previous experiment. The weld zone of bottom did not failure, so the result of numerical analysis is match with the previous experiment. Secondly, this paper based on the regulation, ECE R66(Economic Commission for Europe), to establish a computer simulation of bus rollover test, and used a certain type of Europe bus to study the effect of both the concur rant and the welding failure. Meanwhile, this paper tested whether the Europe bus is match the ECE R66. The result showed that the finite element model of the ideal concurrent way can absorbed energy due to the stiffer structure. When considering the finite element model of the welding effect, due to the failure criteria, the mechanical behavior is more closer to the actual situation. Also, the result showed that both the concurrent and the welding did not pass the regulation ECE R66. Finally, this paper adopted two common size of pipe, 40mm×80mm×3mm and 60mm×40mm×3mm, to study The different impact on structure strength when using different size of ring cross-section. The result showed that the 40mm×80mm×3mm pipe of bus’s ring could pass regulation ECE R66, and the pipe only increased 7.17% of the overall weight. This paper adopted computer simulation which used on equivalent approval method to do the rollover test on complete vehicle. Due to consider the welding failure, the result of this paper is close to the reality. This paper can provide a reference for the bus manufactory to do future manufacturing and design.
Silva, Sebastien Guillaume Victor Blanpain da. "Análise térmica e mecânica do processo Friction Stir Welding." Master's thesis, 2019. http://hdl.handle.net/10316/86548.
Full textA presente dissertação, tem como principal objectivo a análise numérica das condições termomecânicas do processo de soldadura Friction Stir Welding (FSW). Por forma a realizar essa análise, desenvolveram-se dois modelos numéricos, um bidimensional (2D) e outro tridimensional (3D). Aferiu-se a influência do comportamento viscoplástico do material de base nas condições termomecânicas, através da comparação de cinco materiais virtuais distintos, descritos pela lei constitutiva de Norton-Hoff. Avaliou-se também a influência das velocidades de rotação e de avanço da ferramenta nas condições termomecânicas do processo.Os ciclos térmicos, a distribuição da temperatura, o fluxo do material de base e o binário foram analisados na interface entre a ferramenta e o material de base e ao longo da secção transversal do modelo. Deste modo, foi possível relacionar os outputs do processo (temperatura e binário), os parâmetros do processo (velocidades de rotação e avanço da ferramenta) e o comportamento mecânico dos materiais de base.A análise dos resultados permitiu concluir que as condições termomecânicas são fortemente afetadas pelo comportamento mecânico dos materiais de base e pelos parâmetros do processo. De facto, as temperaturas máximas registadas são maioritariamente afetadas pela velocidade de rotação da ferramenta e pelo comportamento mecânico do material de base, enquanto que a velocidade de avanço da ferramenta influencia as taxas de aquecimento e de arrefecimento registadas durante o processo. Verificou-se ainda que as temperaturas máximas mais elevadas resultam em maiores quantidades de fluxo de material devido ao amacimanto do mesmo, e consequentemente, a maiores valores de binário da ferramenta. Também se concluiu que a resistência mecânica dos materiais de base, às temperaturas do processo, tem uma grande influência nas condições termomecânicas do mesmo.
The current dissertation aims the analysis of the thermomechanical conditions during the welding by Friction Stir Welding (FSW) process, using numerical simulation. For this purpose, a two dimensional (2D) and a three dimensional (3D) models were developed. The role of the viscoplastic behaviour of the base material on the thermomechanical conditions was analysed by comparing five distinct virtual materials, described using the Norton-Hoff constitutive law. The influence of tool rotation and welding speeds, on the thermomechanical conditions, were also analysed. Thermal cycles and temperature distribution, on the tool/base material interface and along the model's transverse cross-section, were analysed, as well as the base materials flow and the spindle torque. In this way, it was possible to relate the process outputs (temperature and torque), with the process parameters (tool rotation and welding speeds) and the base materials mechanical behaviour. The results analysis enabled to conclude that the thermomechanical conditions are strongly affected by the base material and the process parameters. In fact, the maximum temperatures registered are mainly governed by the tool rotation speed and the base materials mechanical behaviour, while the welding speed governs the heating and the cooling rates. Higher maximum temperatures lead to higher amounts of material flow due to the material softening, and consequently, to higher spindle torque values. It was also found that the base materials strength, at service temperatures, is the most influencing factor on thermomechanical conditions.
Loureiro, Tiago José Maia. "Exploring the capabilities of Smoothed Particle Hydrodynamics (SPH) in the simulation of manufacturing processes." Master's thesis, 2019. http://hdl.handle.net/10773/31265.
Full textProblemas desafiadores da mecânica computacional podem muitas vezes ser caracterizados por grandes deformações em processos de manufactura, tais como a soldadura por fricção, mais conhecido por ”friction stir welding” (FSW). Os métodos mais comuns, como o método de elementos finitos apresentam grande dificuldade na simulação de grandes deformações, devido à severa distorção presente na malha. Nos últimos anos, métodos que não envolvam malha têm sido uma alternativa aplicada a este tipo de problemas, apontando uma nova geração de métodos computacionais mais eficazes para resolver problemas mais complexos, tais como o método ”Smoothed Particle Hydrodynamics” (SPH). O presente trabalho centra-se na aplicação do método SPH na simulação numérica do processo de soldadura por fricção, com resurso ao software de simulação numérica Abaqus. Contudo o Abaqus apresenta algumas limitações, uma vez que inclui a formulação SPH mas com uma funcionalidade reduzida, não permitindo analisar variações de temperaturas ao longo do processo. De maneira a superar estas limitações foram realizadas várias simulações numéricas com alterações das propriedades do material consoante a temperatura de análise, e do coeficiente de atrito entre o material de trabalho e a ferramenta.
Mestrado em Engenharia Mecânica
Pragosa, Ricardo António Soares. "Simulação Numérica da Soldadura por Impacto de Alumínio-Aço." Master's thesis, 2020. http://hdl.handle.net/10316/92099.
Full textThe present work aims to study, by numerical simulation, using the commercial hydrodynamic program Ansys Autodyn, the morphology and interfacial phenomena in welding aluminum plates to steel by impact. The effect of the impact velocity and the collision angle on the conditions developed at the plate interface, namely on the formation of the jet, on the formation and morphology of waves, the existence of fusion and the temperature and pressure reached, were considered. The numerical results were compared with experimental results obtained in previous studies. The study focused on the bonding of AA 6061-T6 aluminum to AISI 304 stainless steel and high hardness V250 carbon steel.In the Ansys Autodyn simulation software, the mesh method used to reproduce the formation of jet and wave formation more accurately was the Smoothed Particles Hydrodynamics method. The equation of state chosen for the metal plates was the Mie-Grüneisen shock equation, which was associated with the Steinberg-Guinan behavior model. A total of 50 numerical tests were performed.The Al-SS weldability window revealed that the simulations obtained are generally within the weldability limits, with good welding results and interfaces with well-defined waves. It was found that the ideal pressure to obtain the best results was between 2 GPa and 4 GPa. On the contrary, in the Al-CS weldability window, the results obtained in the simulations were not in line with the weldability limits. The interfaces obtained were, in most cases, flat, due to the high hardness of the steel, being quite difficult to connect the two metals. The pressure close to the interface estimated to provide the best welding results was from 4 GPa to 7 GPa.The numerical and experimental results, when compared, did not show total harmony with regard to the morphology of the interface, mainly due to the difference in hardness of welded metals in both approaches.
O presente trabalho tem como objetivo estudar, por simulação numérica, com recurso ao programa comercial hidrodinâmico Ansys Autodyn, a morfologia e os fenómenos interfaciais em soldadura de chapas de alumínio a aço por impacto. Foi considerado o efeito da velocidade de impacto e do ângulo de colisão nas condições desenvolvidas na interface das placas, nomeadamente na formação do jato, na formação e morfologia de ondas, a existência de fusão e a temperatura e pressão atingidas. Os resultados numéricos foram comparados com resultados experimentais obtidos em trabalhos anteriores. O estudo incidiu na ligação do alumínio AA 6061-T6 ao aço inoxidável AISI 304 e ao aço carbono V250 de elevada dureza.No software de simulação Ansys Autodyn, o método de malha utilizado para reproduzir com maior exatidão a formação de jato e de ondas foi o método Smoothed Particles Hydrodynamics. A equação de estado escolhida para as placas metálicas foi a equação de Shock de Mie-Grüneisen, que foi associada ao modelo de comportamento de Steinberg-Guinan. Foram realizados, no total, cerca de 50 ensaios numéricos.A janela de soldabilidade Al-SS revelou que as simulações obtidas estão, de modo geral, dentro dos limites de soldabilidade, com bons resultados de soldadura e interfaces com ondas bem definidas. Verificou-se que a pressão ideal para obter os melhores resultados situava-se entre os 2 GPa e os 4 GPa. Pelo contrário, na janela de soldabilidade Al-CS, os resultados obtidos nas simulações não estavam em sintonia com os limites de soldabilidade. As interfaces obtidas foram, na maior parte dos casos, planas, devido à elevada dureza do aço, sendo bastante difícil ligar os dois metais. A pressão próxima da interface estimada para proporcionar os melhores resultados de soldadura foi de 4 GPa a 7 GPa.Os resultados numéricos e experimentais, quando comparados, não mostraram total sintonia no que respeita à morfologia da interface, devido essencialmente à diferença de dureza dos metais soldados em ambas as abordagens.
Tsai, Min-Chun. "Numerical simulations of heat transfer and fluid flow phenomena in gas tungsten arc welding." 1988. http://catalog.hathitrust.org/api/volumes/oclc/20387808.html.
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