Search results for " Welding"

showing 10 items of 244 documents

FSW of AA2139-T8 Butt joints for aeronautical applications

2011

The effect of process parameters on mechanical and microstructural properties of AA 2139 T8 joints produced by friction stir welding (FSW) was analysed by means of statistical tools. Three different parameters were taken into account: angular speed ( ω), welding speed ( va), and plunging depth ( p); each of them was varied on three levels. Forces and temperatures achieved during the welding were monitored and analysed for all joints. An accurate microstructural analysis was performed: the occurrence of some remarkable defects, typical of FSW, such as tunnel or lack of penetration, was related to actual process parameters adopted. The extension of each FSW characteristic zone was measured a…

Materials scienceMechanical Engineeringmicrostructuredesign of experimentAngular velocityWeldingmechanical propertiesMicrostructureIndentation hardnessfriction stirweldinglaw.inventionanalysis of the variancelawvisual_artUltimate tensile strengthFSW butt joints microstructureAluminium alloyvisual_art.visual_art_mediumButt jointaluminium alloyFriction stir weldingGeneral Materials ScienceComposite materialSettore ING-IND/16 - Tecnologie E Sistemi Di Lavorazione
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Improved FE model for simulation of friction stir welding of different materials

2010

Abstract One of the most relevant aspects of friction stir welding is the possibility to weld different materials. In the present paper, the authors present an improved continuum finite element model for the simulation of friction stir welding processes aimed to obtain T joints, made of a stringer in AA7175-T73511 and of a skin in AA2024-T4. The model, taking into account the thermomechanical behaviours of the two different materials, is utilised to study the occurring material flow and residual stress state. Numerical results are compared with experimental observations: the model is able to predict the material flow, obtaining important information on the joint failure mode.

Materials scienceMechanical engineeringWeldingCondensed Matter PhysicsFriction stir welding T joints Different materials FEMFinite element methodMaterial flowlaw.inventionStringerResidual stresslawFriction stir weldingGeneral Materials ScienceComposite materialSettore ING-IND/16 - Tecnologie E Sistemi Di LavorazioneFailure mode and effects analysisJoint (geology)Science and Technology of Welding and Joining
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Solid state bonding mechanics in extrusion and FSW: Experimental tests and numerical analyses

2007

In the paper the authors compare the different solid state bonding mechanics for both the processes of hollow profiles extrusion and Friction Stir Welding (FSW), through the results obtained from a wide experimental campaign on AA6082-T6 aluminum alloys. Microstructure evaluation, tensile tests and micro-hardness measurements realized on specimens extracted by samples of the two processes are discussed also by means of the results obtained from coupled FEM simulation of the processes. ©2007 American Institute of Physics

Materials scienceMetallurgyFRICTION STIR WELDINGSolid State BondingMechanicsWeldingEXTRUSIONMicrostructureIndentation hardnessFinite element methodlaw.inventionBONDINGlawUltimate tensile strengthFriction stir weldingExtrusionFEM MODELComposite materialSettore ING-IND/16 - Tecnologie E Sistemi Di LavorazioneTensile testing
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Friction Stir Welding of 3D Industrial Parts: Joint Strength Analysis

2006

In the recent years Friction Stir Welding (FSW) has become an important joining technique since it allows to weld light weight alloys rather difficult to be welded or even “un-weldable” with the classic fusion welding operations. In the paper the authors present the application of the FSW process to the joining of 3D complex shapes typical of the industrial environment. In particular the research was aimed to highlight the joint mechanical strength at the varying of the 3D geometry of the welding line.Copyright © 2006 by ASME

Materials scienceMetallurgyFriction Stir WeldingMechanical engineeringWeldingElectric resistance weldinglaw.inventionRobot weldingFusion weldinglawMechanical strengthFriction stir weldingFriction weldingJoint (geology)Settore ING-IND/16 - Tecnologie E Sistemi Di Lavorazione
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Microstructural Changes Determining Joint Strength in Friction Stir Welding of Aluminium Alloys

2005

In the paper the results of a wide experimental activity on friction stir welding (FSW) of aluminum alloys are reported. In particular the butt joints of two different materials, namely AA1050-O and AA6082-T6 were considered. Grains dimensions and precipitates density were investigated both in the parent materials and after the welding processes. Furthermore post-welding heat treatments effects on the joint strength were studied.

Materials scienceMetallurgyGeneral Engineeringchemistry.chemical_elementWeldingMicrostructurelaw.inventionchemistryAluminiumlawButt jointFriction stir weldingComposite materialJoint (geology)Advanced Materials Research
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Thermal Characterization of Friction Stir Welded Butt Joints

2005

In the paper the thermal characterization of friction stir welding processes (FSW) of aluminium alloys is presented. In particular both embedded thermocouples and a thermography analysis were utilized in order to acquire the temperature vs. time curves in point of interests of the joints and the temperature distributions, respectively. Such kind of results are very important in order to investigate the material conditions during the FSW process.

Materials scienceMetallurgyGeneral Engineeringchemistry.chemical_elementWeldinglaw.inventionCharacterization (materials science)chemistryAluminiumThermocouplelawThermographyButt jointFriction stir weldingFriction weldingComposite materialAdvanced Materials Research
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On the influence of tool path in friction stir spot welding of aluminum alloys

2008

Abstract Friction stir spot welding (FSSW) has been proposed as an effective technology to spot weld the so-called “difficult to be welded” metal alloys. In the paper, a variation of the FSSW process has been considered. A tool path is given after the sinking phase nearby the initial penetration site; in this way a larger welding spot is obtained and more material is involved in the bonding process. The process mechanics of such modified FSSW process is highlighted and the joint strength undergoing tensile tests is considered at the varying both of the assigned tool path and of a few process parameters. Macro- and micro-analyses are made in order to analyze the local material microstructure…

Materials scienceMetallurgyMetals and AlloysProcess (computing)Mechanical engineeringchemistry.chemical_elementWeldingMicrostructureIndustrial and Manufacturing EngineeringComputer Science Applicationslaw.inventionTool pathSpotchemistrylawAluminiumModeling and SimulationUltimate tensile strengthCeramics and CompositesWeldingMicrostructureSettore ING-IND/16 - Tecnologie E Sistemi Di LavorazioneJoint (geology)Spot weldingJournal of Materials Processing Technology
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On microstructural phenomena occurring in friction stir welding of aluminium alloys

2006

Abstract The results of experimental activity on friction stir welding (FSW) of aluminum alloys are reported. Butt joints of two different materials, namely AA2024-T4 and AA7075-T6, were investigated from a metallurgical point of view. Grain dimensions and insoluble particle densities were investigated both in the parent materials and in the joints. Furthermore, the effect of post-welding heat treatments on the joint strength was studied.

Materials scienceMetallurgyMetals and Alloyschemistry.chemical_elementWeldingMicrostructureIndustrial and Manufacturing EngineeringComputer Science Applicationslaw.inventionchemistrylawAluminiumModeling and SimulationCeramics and CompositesButt jointFriction stir weldingParticle6063 aluminium alloyComposite materialfriction stir weldingJoint (geology)Journal of Materials Processing Technology
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Numerical support for laser welding of zinc-coated sheets process development

2002

Abstract A lap welding process for zinc-coated sheets has been developed with the help of numerical simulations. This process has been improved and is now compatible with industrial requirements. The zinc boiling point (1180 K) is lower than the steel melting point (1800 K). Consequently, a violent boiling of zinc in melted steel produces serious defects in the seam. To get round this difficulty, we choose to consider a two-spots process: the first spot vaporizes the zinc coating at the interface; the second one welds the sheets. Previously, we develop a numerical model that permits a process parameters choice and limits the plan of experimentations. The zinc ablation spotlight shape is cho…

Materials scienceMetallurgyProcess (computing)General Physics and AstronomyMechanical engineeringLaser beam weldingSurfaces and InterfacesGeneral ChemistryWeldingengineering.materialCondensed Matter PhysicsGalvanizationSurfaces Coatings and Filmslaw.inventionBoiling pointsymbols.namesakeCoatinglawBoilingVaporizationengineeringsymbolsApplied Surface Science
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Laser beam scattering effects in non-absorbent inhomogenous polymers

2007

Ilie, Mariana Kneip, Jean-Christophe Mattei, Simone Nichici, Alexandru Roze, Claude Girasole, Thierry; In this paper a numerical model for laser beam scattering in the semi-transparent polymers is presented, using a Monte Carlo algorithm and the Mie theory. The algorithm correctly accounts for the independent multiply-scattered light. We describe the algorithm, present a number of important parameters that account in the welding process, and explicitly show how the algorithm can be used to estimate the laser beam intensity both inside the semi-transparent component and at the welding interface and the beam widening. For the model validation an experimental bench test has been realized and s…

Materials scienceMonte Carlo method02 engineering and technologyWelding01 natural sciencesBeam parameter productlaw.invention010309 opticsOpticslaw0103 physical sciencesElectrical and Electronic EngineeringMonte Carlo algorithmbusiness.industryMechanical EngineeringLaser beam welding021001 nanoscience & nanotechnologyAtomic and Molecular Physics and OpticsElectronic Optical and Magnetic Materials[SPI.OPTI]Engineering Sciences [physics]/Optics / PhotonicPhysics::Accelerator PhysicsM squaredLaser beam quality0210 nano-technologybusiness0143-8166Beam (structure)
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