A Review on Heat Generation and Temperature Distribution Models in Friction stir Welding (FSW)

Microstructural characterization and temperature analysis have been performed in friction stir welding (FSW) of A383 and 5052 dissimilar aluminum alloys. Marked difference in microstructure was observed between joints with different arrangements of materials. The temperature at four points on each side of the joint line was measured during FSW in various conditions. In addition, an analytical model assumed that the work generated by the rotation of the tool led to the work for stirring materials and heat generation of the material and the tool. The temperature of the retreating side (RS) for the joint of the advancing side (AS):A383/RS:5052 was about 50K higher than that of AS, while the temperatures of AS and RS for the joint of AS:5052/RS:A383 were almost the same. The experimental temperature could be calculated reasonably by using the model with assumption of the work for stirring the material.

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Thermo-mechanical analysis of linear welding stage in friction stir welding - influence of welding parameters

Thermal Science ◽

10.2298/tsci210216186v ◽

2021 ◽

pp. 186-186

Author(s):

Darko Veljic ◽

Marko Rakin ◽

Aleksandar Sedmak ◽

Nenad Radovic ◽

Bojan Medjo ◽

...

Keyword(s):

Friction Stir Welding ◽

Heat Generation ◽

Welding Speed ◽

Reaction Force ◽

Material Model ◽

Element Model ◽

Welding Parameters ◽

Al Alloy ◽

Friction Stir ◽

Fsw Parameters

The influence of friction stir welding (FSW) parameters on thermo-mechanical behaviour of the material during welding is analysed. An aluminium alloy is considered (Al 2024 T351), and different rotating speed and welding speed are applied. Finite element model consists of the plate (Al alloy), backing plate and welding tool, and it is formed and solved in software package Simulia Abaqus. The influence of the welding conditions on material behaviour is taken into account by application of the Johnson-Cook material model. The rotation of the tool affects the results: if increased, it contributes to an increase of friction-generated heat intensity. The other component of the generated heat, the plastic deformation of the material, is negligibly changed. When the welding speed is increased, the intensity of friction-generated heat decreases, while the heat generation due to plastic deforming increases. Combined, these two effects cause small change of the total heat generation. For the same welded joint length, the plate welded by lower speed will be heated more intensively. The changes of the heat generation influence both the temperature field and reaction force, which are also considered.

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

Thermal Science ◽

10.2298/tsci150313059v ◽

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.

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A Modified Analytical Heat Source Model for Numerical Simulation of Temperature Field in Friction Stir Welding

Advances in Materials Science and Engineering ◽

10.1155/2020/4639382 ◽

2020 ◽

Vol 2020 ◽

pp. 1-16

Author(s):

Xiangqian Liu ◽

Yan Yu ◽

Shengli Yang ◽

Huijie Liu

Keyword(s):

Heat Flux ◽

Friction Stir Welding ◽

Analytical Model ◽

Heat Generation ◽

Tilt Angle ◽

Temperature Fields ◽

Analytical Models ◽

Maximum Temperature ◽

Thermal Cycles ◽

Friction Stir

In the conventional analytical model used for heat generation in friction stir welding (FSW), the heat generated at the pin/workpiece interface is assumed to distribute uniformly in the pin volume, and the heat flux is applied as volume heat. Besides, the tilt angle of the tool is assumed to be zero for simplicity. These assumptions bring about simulating deviation to some extent. To better understand the physical nature of heat generation, a modified analytical model, in which the nonuniform volumetric heat flux and the tilt angle of the tool were considered, was developed. Two analytical models are then implemented in the FEM software to analyze the temperature fields in the plunge and traverse stage during FSW of AA6005A-T6 aluminum hollow extrusions. The temperature distributions including the maximum temperature and heating rate between the two models are different. The thermal cycles in different zones further revealed that the peak temperature and temperature gradient are very different in the high-temperature region. Comparison shows that the modified analytical model is accurate enough for predicting the thermal cycles and peak temperatures, and the corresponding simulating precision is higher than that of the conventional analytical model.

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