scholarly journals Analysis of the tool plunge in friction stir welding - comparison of aluminium alloys 2024 T3 and 2024 T351

2016 ◽  
Vol 20 (1) ◽  
pp. 247-254
Author(s):  
Darko Veljic ◽  
Bojan Medjo ◽  
Marko Rakin ◽  
Zoran Radosavljevic ◽  
Nikola Bajic
Keyword(s):  
Friction Stir Welding ◽  
Plastic Strain ◽  
Heat Generation ◽  
Aluminium Alloys ◽  
Three Dimensional ◽  
Equivalent Plastic Strain ◽  
Fe Model ◽  
Arbitrary Lagrangian Eulerian ◽  
Friction Stir ◽  
Tool Pin

Temperature, plastic strain and heat generation during the plunge stage of the friction stir welding (FSW) of high-strength aluminium alloys 2024 T3 and 2024 T351 are considered in this work. The plunging of the tool into the material is done at different rotating speeds. A three-dimensional finite element (FE) model for thermomechanical simulation is developed. It is based on arbitrary Lagrangian-Eulerian formulation, and Johnson-Cook material law is used for modelling of material behaviour. From comparison of the numerical results for alloys 2024 T3 and 2024 T351, it can be seen that the former has more intensive heat generation from the plastic deformation, due to its higher strength. Friction heat generation is only slightly different for the two alloys. Therefore, temperatures in the working plate are higher in the alloy 2024 T3 for the same parameters of the plunge stage. Equivalent plastic strain is higher for 2024 T351 alloy, and the highest values are determined under the tool shoulder and around the tool pin. For the alloy 2024 T3, equivalent plastic strain is the highest in the influence zone of the tool pin.

A New Approach to Measure Strain During Friction Stir Welding Using Visioplasticity

2011 ◽  
Author(s):  
Mohamadreza Nourani ◽  
Abbas S. Milani ◽  
Spiro Yannacopoulos
Keyword(s):  
Friction Stir Welding ◽  
Plastic Strain ◽  
Shape Change ◽  
Equivalent Plastic Strain ◽  
Leading Edge ◽  
Strain Range ◽  
New Approach ◽  
Friction Stir ◽  
Tool Shoulder ◽  
Tool Pin

During modeling of the friction stir welding (FSW) process, the prediction of strain range experienced by the material is important as it affects the microstructure and mechanical properties of the final weld [1–7]. For aluminum alloys, this range has been reported very scarcely and/or scattered widely in the literature (the range of the maximum equivalent plastic strain has been reported to be from 2.4 to 184 [8–24]). A new approach is proposed in this article for measuring strain during friction stir welding using visioplasticity. In this approach, strains are calculated from changes in the boundaries of a small cylindrical Al-30% SiC composite marker mounted in the advancing side of mid-plane of adjacent plates during welding. The marker shape change is observed by a “stop action” (freeze-in) technique midway the process. COMSOL numerical modeling is then used to compute the strain distribution using the observed boundary changes compared to the initial marker boundaries. As an illustrative example, the method is applied to the results reported by London et al. [25] for the friction stir welding of 6.35 mm thick 7050 aluminum plates, welded with tool RPM of 350, welding speed of 1.69 mm/sec, tool pin diameter of 8 mm, tool shoulder diameter of 24 mm, and tool tilt angle of 3 degrees. A lower and upper bound of cumulative equivalent plastic strain of 14.1 and 20.3, respectively, were found to be in the neighborhood where the marker enters the severe deformation zone at mid-plane of plates in front of the leading edge of the pin.

scholarly journals A coupled thermo-mechanical model of friction stir welding

2012 ◽  
Vol 16 (2) ◽  
pp. 527-534 ◽  
Author(s):  
Darko Veljic ◽  
Milenko Perovic ◽  
Aleksandar Sedmak ◽  
Marko Rakin ◽  
Miroslav Trifunovic ◽  
...  
Keyword(s):  
Friction Stir Welding ◽  
Plastic Strain ◽  
Mechanical Model ◽  
Temperature Fields ◽  
Maximum Temperature ◽  
Bottom Surface ◽  
Al Alloy ◽  
Fe Model ◽  
Arbitrary Lagrangian Eulerian ◽  
Friction Stir

A coupled thermo-mechanical model was developed to study the temperature fields, the plunge force and the plastic deformations of Al alloy 2024-T351 under different rotating speed: 350, 400 and 450 rpm, during the friction stir welding (FSW) process. Three-dimensional FE model has been developed in ABAQUS/Explicit using the arbitrary Lagrangian-Eulerian formulation, the Johnson-Cook material law and the Coulomb?s Law of friction. Numerical results indicate that the maximum temperature in the FSW process is lower than the melting point of the welding material. The temperature filed is approximately symmetrical along the welding line. A lower plastic strain region can be found near the welding tool in the trailing side on the bottom surface. With increasing rotation speed, the low plastic strain region is reduced. When the rotational speed is increased, the plunge force can be reduced. Regions with high equivalent plastic strains are observed which correspond to the nugget and the flow arm.

Optimization of friction stir welding parameters of dissimilar aluminium alloys 6061 and 5083 by using response surface methodology

2021 ◽  
pp. 095440622110058
Author(s):  
Sanjeev Verma ◽  
Vinod Kumar
Keyword(s):  
Tensile Strength ◽  
Friction Stir Welding ◽  
Tilt Angle ◽  
Feed Rate ◽  
Aluminium Alloys ◽  
Welded Joint ◽  
Welding Parameters ◽  
Friction Stir ◽  
Industrial Sectors ◽  
Tool Pin

Aluminium and its alloys are lightweight, corrosion-resistant, affordable and high-strength material and find wide applications in shipbuilding, automotive, constructions, aerospace and other industrial sectors. In applications like aerospace, marine and automotive industries, there is a need to join components made of different aluminium alloys, viz. AA6061 and AA5083. In this study friction stir welding (FSW) is used to join dissimilar plates made of AA6061-T6 and AA5083-O. The effect of varying tool pin profile, tool rotation speed, tool feed rate and tilt angle of the tool has been investigated on the tensile strength and percentage elongation of the welded joints. Box-Behkan design, with four input parameters and three levels of each parameter has been employed to decide the set of experimental runs. The regression models have been developed to investigate the influence of welding variables on the tensile strength and elongation of the welded joint. It is revealed that with the increase in welding parameters like tool rpm, tool feed rate and tilt angle of the tool, both the mechanical properties increase, reach a maximum level, followed by a decrease with further increase in the value of parameters. Amongst different types of tool pin profiles used, the FSW tool having straight cylindrical (SC) pin profile is found to yield the maximum strength and elongation of the welded joint for different combinations of welding parameters. Multiple response optimization indicates that the maximum UTS (135.83 MPa) and TE (4.35%) are obtained for the welded joint fabricated using FSW tool having SC pin profile, tilted at 1.11° and operating at tool speed and feed rate of 1568 rpm and 39.53 mm/min., respectively.

Effect of Tool pin Profile and Axial Force on Tensile Behavior in Friction Stir Welding of Dissimilar Aluminum Alloys

2011 ◽  
Vol 415-417 ◽  
pp. 1140-1146 ◽  
Author(s):  
R. Palanivel ◽  
P. Koshy Mathews ◽  
M. Balakrishnan ◽  
I. Dinaharan ◽  
N. Murugan
Keyword(s):  
Tensile Strength ◽  
Friction Stir Welding ◽  
Axial Force ◽  
Aluminium Alloys ◽  
Welding Process ◽  
Fusion Welding ◽  
Friction Stir ◽  
Tool Pin Profile ◽  
Dissimilar Aluminum Alloys ◽  
Tool Pin

Aluminium alloys generally has low weldability by traditional fusion welding process. The development of the Friction Stir Welding (FSW) has provided an alternative improved way of producing aluminium joints, in a faster and reliable manner. FSW process has several advantages, in particular the possibility to weld dissimilar aluminium alloys. This study focuses on the behavior of tensile strength of dissimilar joints of AA6351-T6 alloy to AA5083-H111 alloy produced by friction stir welding was analysed. Five different tool pin profile such as Straight Square (SS), Tapered Square (TS), Straight Hexagon (SH), Straight Octagon (SO) and Tapered Octagon (TO) with three different axial force (1tonne, 1.5tonne, 2 tonne) have been used to weld the joints. The effect of pin profiles and axial force on tensile properties and material flow behaviour of the joint was analyzed and it was found that the straight square pin profile with 1.5 tonne produced better tensile strength then other tool pin profile and axial force.

scholarly journals Numerical Studies on Temperature and Material Flow During Friction Stir Welding using Different Tool Pin Profiles

2021 ◽  
Vol 83 (1) ◽  
pp. 91-104
Author(s):  
M. D. Bindu ◽  
P. S. Tide ◽  
A. B. Bhasi
Keyword(s):  
Friction Stir Welding ◽  
Temperature Distribution ◽  
Material Flow ◽  
Three Dimensional ◽  
Friction Stir ◽  
Specific Strength ◽  
Numerical Studies ◽  
Computational Fluid Dynamics Cfd ◽  
Tool Pin ◽  
Metal Hardness

A three dimensional computational fluid dynamics (CFD) model has been developed to study the effect of tool pin profile on the material flow and temperature development in friction stir welding (FSW) of high specific strength AA 7068 alloy. Numerical simulations were carried out using a RNG k-e turbulence model. Three tool pin profiles, viz. cylindrical, conical and straight cylindrical threaded were considered for the simulation. The temperature distribution and material flow pattern obtained from the simulation were compared for different pin profiles. Simulation results predicted Temperature distribution and material maxing was better in straight cylindrical tapered thread pin welds. Weld joints were fabricated using the straight cylindrical threaded pin with the same parametric combinations as in the simulation. Peak temperature measured in the experiment was less than that obtained by simulation. Hardness measurements taken at different weld regions has showed that about 71% of that of the base metal hardness is obtained with the threaded tool pin. The microstructure study revealed a defect free weld joint. Precipitates distributed in the microstructure indicate sufficient heat input to join the material without dissolving precipitates. The developed numerical model is helpful in optimising FSW process parameters.

A thermal-plastic model of friction stir welding in aluminum alloy

2017 ◽  
Vol 24 (3) ◽  
pp. 439-446
Author(s):  
Zhang Peilei ◽  
Yan Hua ◽  
Li Chonggui ◽  
Yu Zhishui ◽  
Lu Qinghua
Keyword(s):  
Plastic Deformation ◽  
Friction Stir Welding ◽  
Three Dimensional ◽  
Transfer Model ◽  
Friction Stir ◽  
Tool Shoulder ◽  
Moving Coordinate ◽  
Model Of Friction ◽  
Tool Pin ◽  
Good Agreement

AbstractA three-dimensional heat transfer model for friction stir welding is presented in this paper. A moving coordinate was introduced to reduce the difficulty of modeling the moving tool. Heat input from the tool shoulder and the tool pin were considered in the model. The plastic deformation heat was introduced into the model, too. It is clear that the heat production increased owing to plastic deformation, and this process depends on the stress level. Temperature measurement experiments were done to validate the calculated results. The calculated results were in good agreement with the experimental results. Preheating the workpiece is beneficial to obtain a good weld seam.

scholarly journals Heat generation during plunge stage in friction stir welding

2013 ◽  
Vol 17 (2) ◽  
pp. 489-496 ◽  
Author(s):  
Darko Veljic ◽  
Marko Rakin ◽  
Milenko Perovic ◽  
Bojan Medjo ◽  
Zoran Radakovic ◽  
...  
Keyword(s):  
Friction Stir Welding ◽  
Heat Generation ◽  
Slip Rate ◽  
Element Model ◽  
Numerical Results ◽  
Frictional Heat ◽  
Al Alloy ◽  
Arbitrary Lagrangian Eulerian ◽  
Workpiece Material ◽  
Friction Stir

This paper deals with the heat generation in the Al alloy Al2024-T3 plate under different rotating speeds and plunge speeds during the plunge stage of friction stir welding (FSW). A three-dimensional finite element model (FEM) is developed in the commercial code ABAQUS/Explicit using the arbitrary Lagrangian-Eulerian formulation, the Johnson-Cook material law and Coulomb?s Law of friction. The heat generation in FSW can be divided into two parts: frictional heat generated by the tool and heat generated by material deformation near the pin and the tool shoulder region. Numerical results obtained in this work indicate a more prominent influence from the friction-generated heat. The slip rate of the tool relative to the workpiece material is related to this portion of heat. The material velocity, on the other hand, is related to the heat generated by plastic deformation. Increasing the plunging speed of the tool decreases the friction-generated heat and increases the amount of deformation-generated heat, while increasing the tool rotating speed has the opposite influence on both heat portions. Numerical results are compared with the experimental ones, in order to validate the numerical model, and a good agreement is obtained.

scholarly journals Pin Angle Thermal Effects on Friction Stir Welding of AA5058 Aluminum Alloy: CFD Simulation and Experimental Validation

Materials ◽  
2021 ◽  
Vol 14 (24) ◽  
pp. 7565
Author(s):  
Supat Chupradit ◽  
Dmitry Olegovich Bokov ◽  
Wanich Suksatan ◽  
Michał Landowski ◽  
Dariusz Fydrych ◽  
...  
Keyword(s):  
Friction Stir Welding ◽  
Heat Generation ◽  
Cfd Simulation ◽  
Fluid Dynamic ◽  
Critical Role ◽  
Internal Heat ◽  
Mechanical Action ◽  
Friction Stir ◽  
Pin Geometry ◽  
Tool Pin

The friction stir welding (FSW) of tool pin geometry plays a critical role in the final properties of the produced joint. The tool pin geometry directly affects the generation of heat and the flow of internal materials during the FSW process. The effects of the FSW tool pin angle on heat generation and internal flow have not been quantitatively investigated in detail. In this manuscript, a validated Computational Fluid Dynamic (CFD) model was implemented to analyze the effects of pin angle on the thermo-mechanical action during the FSW process of AA5058 Al-Mg alloy. Experimental test results validate the thermal outcomes of the used model. The obtained results revealed that, when the pin angle is increased, the heat generation decreases while the mechanical action of the tool increases. The internal heat distribution at a higher pin angle is symmetrical. The higher mechanical action of the tool decreases the viscosity of the internal materials and increases stirring action (materials flow) around the pin. Furthermore, plastic flow near the tool increased stirring action and formed a larger stir zone in the joint area.

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