Temperature Distribution Analysis in Plates Joined by Friction Stir Welding

Author(s):  
Mauricio Rangel Pacheco ◽  
Jean Paul Kabche ◽  
Ivan Thesi ◽  
Fabiano Nunes Diesel

Friction Stir Welding (FSW) is a solid-state welding process which generates heat through mechanical friction between a moving workpiece and a fixed component, in order to plastically combine materials. This process has been gaining considerable attention due to several key advantages, which include: good mechanical properties of the combined materials after welding, absence of toxic fumes and molten material spatter, low environmental impact, and low concentration of defects while allowing a large variation of parameters and materials. Although a reasonable number of experimental investigations on FSW are available in the literature, numerical modeling of this process has not been performed on a large scale. In that light, this paper presents a numerical investigation of the temperature distribution in plates welded by FSW, using finite element analysis. The finite element model developed includes friction between the workpiece and the fixed component, as well as the corresponding heat dissipation that results from plastic deformation of the material. The model was found appropriate for estimating important welding characteristics, such as the heat-affected zone (HAZ), and their sensitivity to various welding parameters.

2013 ◽  
Vol 758 ◽  
pp. 11-19 ◽  
Author(s):  
Mauricio Rangel Pacheco ◽  
Pedro Manuel Calas Lopes Pacheco

Welding is a fabrication process widely used in several industrial areas. The welding of metallic alloys presents some basic characteristics as the presence of a localized intensive heat input that promotes mechanical and metallurgical changes. Different from conventional welding processes, where macroscopic fusion is observed, friction welding is a solid state welding process where the joint is produced by the relative rotational and/or translational motion of two pieces under the action of compressive forces producing heat and plastic strain on the friction surfaces. Friction Stir Welding (FSW) process has received much attention for its special characteristics, like the high quality of the joints. Although there are several experimental works on the subject, numerical modeling is not well stated, as the process is very complex involving the coupling of several non-linear phenomena. In this contribution a tridimensional finite element model is presented to study the temperature distribution in plates welded by the FSW process. A weld heat source is proposed to represent the heat generated during the process. The heat source model considers several contributions present in the process as the friction between the tool and the piece and the plastic power associated to the plastic strain developed. Numerical results show that the model is in close agreement with experimental results, indicating that the model is capable of capturing the main characteristics of the process. The proposed model can be used to predict important process characteristics, like the TAZ (Thermal Affected Zone), as a function of the welding parameters.


2016 ◽  
Vol 687 ◽  
pp. 155-162
Author(s):  
Piotr Lacki ◽  
Zygmunt Kucharczyk ◽  
Tomasz Walasek

In the paper, the influence of friction on temperature distribution in the friction spot stir welding process of titanium grade 2 is analysed. It is assumed that the friction coefficient may be a function of temperature or the relative speed of the contact areas. The finite element method is used in the numerical calculations. Temperature distributions and temperature versus time for the analysed friction coefficients are presented. The results also show that applying a proper frictional model is very essential for the sake of heat generation during friction stir welding.


2010 ◽  
Vol 44-47 ◽  
pp. 76-80
Author(s):  
Lei Wang ◽  
Jian Jun Zhu

Temperature distribution is the foundation to study friction stir welding technique, influence of welding parameters on temperature was studied through experiment measurement on AA2024-T4 aluminum alloy plates. An instantaneous relative linear velocity based heat source was utilized to build the FEM model of friction stir welding process, good agreement was observed between the measured and simulated thermal profiles. FEM model was also utilized to study effect of welding parameters on temperature distribution.


2004 ◽  
Vol 824 ◽  
Author(s):  
Therese Källgren ◽  
Lai-Zhe Jin ◽  
Rolf Sandström

AbstractIn an effort to enhance safety for long time disposal of waste nuclear fuel, friction stir welding has been developed as one alternative to seal copper canisters. To avoid the formation of voids and cracks during the welding process, an understanding of the heat and material flow andthereby the evolution of the microstructure, is of great importance. Finite element modelling has been used to simulate the heat and material flow as well as thermal expansion during the friction stir welding process. A model involving heat transfer, material flow, and continuum mechanics has been developed. The steady state solutions have been compared with experimental temperature observations as well as analytical solutions, showing good agreement. Temperature distribution is affected by the welding speed. For a given reference pointperpendicular to the welding direction, a lower welding speed corresponds to a higher peak temperature. The plunging position of welding tool influences the temperature distribution and therefore the displacement distribution of the weldment.


2012 ◽  
Vol 622-623 ◽  
pp. 323-329
Author(s):  
Ebtisam F. Abdel-Gwad ◽  
A. Shahenda ◽  
S. Soher

Friction stir welding (FSW) process is a solid state welding process in which the material being welded does not melt or recast. This process uses a non-consumable tool to generate frictional heat in the abutting surfaces. The welding parameters and tool pin profile play major roles in deciding the weld quality. In this investigation, an attempt has been made to understand effects of process parameters include rotation speeds, welding speeds, and pin diameters on al.uminum weldment using double shoulder tools. Thermal and tensile behavior responses were examined. In this direction temperatures distribution across the friction stir aluminum weldment were measured, besides tensile strength and ductility were recorded and evaluated compared with both single shoulder and aluminum base metal.


Author(s):  
Debtanay Das ◽  
Swarup Bag ◽  
Sukhomay Pal ◽  
M. Ruhul Amin

Abstract Friction stir welding (FSW) is widely recognized green manufacturing process capable of producing good quality welded joints at temperature lower than the melting point. However, most of the works is focused on to the establishment of the process parameters for a defect-free joint. There is a lack to understand the formation of defects from physical basis and visualization of the same, which is otherwise difficult to predict by means of simple experiments. The conventional models do not predict chip formation and surface morphology by accounting the material loss during the process. Hence, a 3D finite element based thermo-mechanical model is developed following Coupled Eulerian-Lagrangian (CEL) approach to understand surface morphology by triggering material flow associated with tool-material interaction. In the present quasi-static analysis, the mass scaling factor is explored to make the model computationally feasible by varying the FSW parameter of plunge depth. The simulated results are validated with experimentally measured temperature and surface morphology. In CEL approach, the material flow out of the workpiece enables the visualization of the chip formation, whereas small deformation predict the surface quality of the joint.


Sign in / Sign up

Export Citation Format

Share Document