Friction stir welding (FSW) simulation using an arbitrary Lagrangian -Eulerian (ALE) moving mesh approach

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.

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Numerical Simulation of Friction Stir Welding of Aluminum Alloys: A Brief Review

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.809-810.467 ◽

2015 ◽

Vol 809-810 ◽

pp. 467-472

Author(s):

Marius Adrian Constantin ◽

Ana Boşneag ◽

Monica Iordache ◽

Eduard Niţu ◽

Doina Iacomi

Keyword(s):

Numerical Simulation ◽

Friction Stir Welding ◽

Aluminum Alloys ◽

Copper Alloys ◽

Tool Geometry ◽

Friction Stir ◽

Complex Process ◽

Scientific Papers ◽

Fsw Simulation ◽

Aluminum And Magnesium Alloys

Friction Stir Welding (FSW) is the latest innovative and most complex process which is widely applied to the welding of lightweight alloys, such as aluminum and magnesium alloys, and most recently, titanium alloys, copper alloys, steels and super-alloys. Friction stir welding is a highly complex process comprising several highly coupled physical phenomena. The experiments are often time consuming and costly. To overcome these problems, numerical analysis has frequently been used in the last ten years. In this paper is presented a brief review of scientific papers in recent years on numerical simulation of Friction Stir Welding of aluminum alloys. The main elements analyzed by FSW simulation, and briefly in this paper are: temperature and residual stress distribution; work tool geometry (size and shape of the pin); distribution of equivalent plastic deformation; main areas resulted after welding; distribution of microstructure (grain size); parameters and optimization of the FSW process.

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Numerical Simulation of Friction Stir Welding (FSW) Process Based on ABAQUS Environment

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.254.272 ◽

2016 ◽

Vol 254 ◽

pp. 272-277

Author(s):

Monica Iordache ◽

Claudiu Bădulescu ◽

Eduard Niţu ◽

Doina Iacomi

Keyword(s):

Numerical Simulation ◽

Friction Stir Welding ◽

Finite Elements ◽

Adaptive Mesh ◽

Experimental Tests ◽

Arbitrary Lagrangian Eulerian ◽

Complex Issue ◽

Friction Stir ◽

Mechanical Phenomena

. Simulation of the FSW process is a complex issue, as it implies interactions between thermal and mechanical phenomena and the quality of the welding depends on many factors. In order to reduce the time of the experimental tests, which can be long and expensive, numerical simulation of the FSW process has been tried during the last ten years. However, there still remain aspects that cannot be completely simulated. In this paper the authors present the steps of the numerical simulation using the finite elements method, in order to evaluate the boundary conditions of the model and the geometry of the tools by using the Arbitrary Lagrangian Eulerian (ALE) adaptive mesh controls.

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Investigation of Vibration Assisted Friction Stir Welding

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.504-506.741 ◽

2012 ◽

Vol 504-506 ◽

pp. 741-746 ◽

Cited By ~ 8

Author(s):

Hamid Montazerolghaem ◽

Mohsen Badrossamay ◽

Alireza Fadaei Tehrani

Keyword(s):

Friction Stir Welding ◽

Axial Force ◽

Process Condition ◽

Welding Process ◽

High Strength ◽

State Spaces ◽

Friction Stir ◽

Fsw Simulation ◽

Resultant Forces ◽

Welding Force

Friction Stir Welding (FSW) is a relatively new solid state joining method that can be used to achieve very good weld quality. This technique is energy efficient, environment friendly, and versatile. The FSW process utilizes a rotating tool in which includes a pin and shoulder to perform the welding process. FSW applications in high strength alloys, such as stainless steel remain limited due to large welding force and consequent tool wear. It has been shown that applying the ultrasonic vibration on some processes such as turning and drilling the resultant forces are decreased and process condition is improved. In this paper the influence of applying vibration on FSW is investigated in simulating tools. For FSW modeling a proper transfer function of axial force has been proposed. The resultant axial force of conventional FSW and Vibration Assisted FSW (VAFSW) are compared in frequency and time domain state spaces. A good correlation between FSW simulation and experiments is observed. For further investigation of VAFSW the response surface of design of experiment (DOE) method is utilized. The influence of changing VAFSW process parameters is investigated. The simulation results indicate that vibration helps to decrease the welding force. Using DOE method the effects of implemented frequency and vibration speed amplitude in FSW are found.

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Temperature fields in linear stage of friction stir welding: Effect of different material properties

Thermal Science ◽

10.2298/tsci181015264v ◽

2019 ◽

Vol 23 (6 Part B) ◽

pp. 3985-3992

Author(s):

Darko Veljic ◽

Marko Rakin ◽

Bojan Medjo ◽

Mihailo Mrdak ◽

Aleksandar Sedmak

Keyword(s):

Friction Stir Welding ◽

Numerical Models ◽

Welding Process ◽

High Strength ◽

Temperature Fields ◽

Arbitrary Lagrangian Eulerian ◽

Friction Stir ◽

Strain And Strain Rate ◽

The Difference ◽

Weld Area

Friction stir welding is one of the procedures for joining the parts in solid state. Thermo-mechanical simulation of the friction stir welding of high-strength aluminium alloys 2024 T3 and 2024 T351 is considered in this work. Numerical models corresponding to the linear welding stage are developed in Abaqus software package. The material behaviour is modelled by Johnson-Cook law (which relates the yield stress with temperature, strain and strain rate), and the Arbitrary Lagrangian-Eulerian technique is applied. The difference in thermo-mechanical behaviour between the two materials has been analysed and commented. The main quantities which are considered are the temperature in the weld area, plastic strain, as well as the rate of heat generation during the welding process.

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Heat generation during plunge stage in friction stir welding

Thermal Science ◽

10.2298/tsci120301205v ◽

2013 ◽

Vol 17 (2) ◽

pp. 489-496 ◽

Cited By ~ 18

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.

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Two different finite element models investigation of the plunge stage in joining AZ31B magnesium alloy with friction stir welding

SN Applied Sciences ◽

10.1007/s42452-021-04191-6 ◽

2021 ◽

Vol 3 (2) ◽

Author(s):

Murat Turkan ◽

Özler Karakas

Keyword(s):

Finite Element ◽

Friction Stir Welding ◽

Magnesium Alloy ◽

Rotational Speed ◽

Processing Time ◽

Lagrangian Formulation ◽

Finite Element Models ◽

Arbitrary Lagrangian Eulerian ◽

Friction Stir ◽

Eulerian Formulation

AbstractThis study presents an investigation of the plunge stage in joining AZ31B magnesium alloy with friction stir welding using two different 3D finite element models based on Arbitrary Lagrangian–Eulerian formulation and Coupled Eulerian–Lagrangian formulation. The investigations are made with the ABAQUS program. Johnson–Cook plastic material law and Coulomb friction law are used in both models. Models are compared in terms of temperature, strain distribution, and processing time. In both models, very similar temperature and strain distributions are obtained in the weld zone and the models are validated by experimental results. In addition, with the increase in the rotational speed of the tool, temperature and strain in the welding zone increase similarly in both models. In the model using the Arbitrary Lagrangian–Eulerian formulation, mesh distortions occur when high mesh density is not created in the plunge zone. No problems related to mesh distortion are encountered in the model using Coupled Eulerian–Lagrangian formulation. Moreover, it is found that the model using the Coupled Eulerian–Lagrangian formulation has a lower processing time and this processing time is not affected by the rotational speed of the tool.

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Experimental and numerical thermo-mechanical analysis of friction stir welding of high-strength alluminium alloy

Thermal Science ◽

10.2298/tsci130512171v ◽

2014 ◽

Vol 18 (suppl.1) ◽

pp. 29-38 ◽

Cited By ~ 5

Author(s):

Darko Veljic ◽

Aleksandar Sedmak ◽

Marko Rakin ◽

Nikola Bajic ◽

Bojan Medjo ◽

...

Keyword(s):

Friction Stir Welding ◽

Welding Process ◽

Vertical Direction ◽

High Strength ◽

Temperature Fields ◽

Bottom Surface ◽

Arbitrary Lagrangian Eulerian ◽

Welding Zone ◽

Friction Stir ◽

Tool Shoulder

This paper presents experimental and numerical analysis of the change of temperature and force in the vertical direction during the friction stir welding of high-strength aluminium alloy 2024 T3. This procedure confirmed the correctness of the numerical model, which is subsequently used for analysis of the temperature field in the welding zone, where it is different to determine the temperature experimentally. 3D finite element model is developed using the software package Abaqus; arbitrary Lagrangian-Eulerian formulation is applied. Johnson-Cook material law and Coulomb?s Law of friction are used for modelling the material behaviour. Temperature fields are symmetrical with respect to the welding line. The temperature values below the tool shoulder, i.e. in the welding zone, which are reached during the plunge stage, are approximately constant during the entire welding process and lie within the interval 430-502?C. The temperature of the material in the vicinity of the tool is about 500?C, while the values on the top surface of the welding plates (outside the welding zone, but close to the tool shoulder) are about 400?C. The temperature difference between the top and bottom surface of the plates is small, 10-15?C.

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Investigation of material flow and thermomechanical behavior during friction stir welding of an AZ31B alloy for threaded and unthreaded pin geometries using computational solid mechanics simulation

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1177/0954406220962540 ◽

2020 ◽

pp. 095440622096254

Author(s):

RAR Giorjao ◽

EB Fonseca ◽

JA Avila ◽

EF Monlevade ◽

AP Tschiptschin

Keyword(s):

Friction Stir Welding ◽

Material Flow ◽

Solid Mechanics ◽

Defect Formation ◽

Welding Process ◽

High Sensitivity ◽

Thermomechanical Behavior ◽

Welding Parameters ◽

Arbitrary Lagrangian Eulerian ◽

Friction Stir

In the friction stir welding process, the tool role in the material flow and its thermomechanical behavior is still not entirely understood. Several modeling approaches attempted to explain the material and tool relationship, but to this date, insufficient results were provided in this matter. Regarding this issue and the urgent need for trustful friction stir welding models, a computational solid mechanic's model capable of simulating material flow and defect formation is presented. This model uses an Arbitrary Lagrangian-Eulerian code comparing a threaded and unthread pin profile. The model was able to reproduce the tool's torque, temperatures, and material flow along the entire process, including the underreported downward flow effect promoted by threaded pin's. A point tracking analysis revealed that threads increase the material velocity and strain rate to almost 30% compared to unthreaded conditions, promoting a temperature increment during the process, which improved the material flow and avoided filling defects. The presented results showed the model's capability to reproduce the defects observed in real welded joints, material thermomechanical characteristics and high sensitivity to welding parameters and tool geometries. Nevertheless, the outcomes of this work contribute to essential guidelines for future friction stir welding modeling and development, tool design, and defect prediction.

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