Numerical Simulation Model for FSW Employing Particle Method – Effect of Tool Angle on Fluid Motion

2014 ◽  
Vol 783-786 ◽  
pp. 1765-1769 ◽  
Author(s):  
Fumikazu Miyasaka ◽  
Gaku Yoshikawa ◽  
Shuhei Matsuzawa

The friction stir welding (FSW) is known as non-melting joining. It used widely in the field of industry. Numerical analysis models for FSW also have been developed. In these models, the most frequently used method is a grid method (finite element method or finite difference method). However it is difficult or troublesome to calculate the advective term both for momentum and temperature employing these methods. It is also difficult to calculate the big deformation of the material's free surface. Moreover, complex process is required to analyze the dissimilar joining with respect to dealing with substance transfer. In this paper, to avoid these difficulties, particle method is adopted for FSW simulation. In particle method, advective term, substance transfer, and surface deformation are calculated automatically mainly because that Lagrangian approach is used. To verify the effectiveness of this method, fluid motion around the tool is examined by particle trace. As a result, relations between the rotating speed of the tool and area of plastic flow is evaluated.

2015 ◽  
Vol 809-810 ◽  
pp. 467-472
Author(s):  
Marius Adrian Constantin ◽  
Ana Boşneag ◽  
Monica Iordache ◽  
Eduard Niţu ◽  
Doina Iacomi

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.


2021 ◽  
Vol 880 ◽  
pp. 57-62
Author(s):  
Normariah Che Maideen ◽  
Salina Budin ◽  
Koay Mei Hyie ◽  
Nor Azirah Mohd Fohimi

Stirring tool is one of the important factor that contribute to the successful of Friction Stir Welding (FSW). Role of tool, is to heat the welding zone and stir the material along the process. Many studies have been conducted by other researchers to improve the performance of stirring tool. Similar to this work, it is aimed to investigate and analyze the effect of stirring tool surface condition on wear characteristics in friction stir welding process. Four tools have been fabricated with pre-determined surface condition. Tool 1: H13 without heat treatment and without coating. Tool 2: H13 with heat treatment only. Tool 3: H13 with TiCN coating only and Tool 4: H13 with heat treatment and with TiCN coating. Friction stir welding was performed to test and verify the performance of fabricated tools. Process parameter used are 1270 RPM for rotating speed while 218 mm/min for welding speed. From the result, Tool 4 performed better in terms of physical wear as well as wear rate.


2009 ◽  
Vol 68 ◽  
pp. 167-174 ◽  
Author(s):  
Jerry Wong ◽  
Patricia del C. Zambrano ◽  
Martha Patrizia Guerrero-Mata ◽  
Victor Mucino ◽  
Rafael Colás

A series of linear and spot stir welding friction tests were carried out on aluminum samples of 1 mm in thickness and area of 100 mm x 27 mm. The tool rotating speed was varied from 2000 to 4000 RPM and the feeding rate from 45 to 67.8 mm/min. The temperature distribution during welding was measured by thermocouples inserted within the aluminum strips. The microstructure of the welded nuggets and the HAZ were analyzed by optical and scanning electron microscopy. Some samples were tested intension to measure the load carrying capacity of the welded bead. Preliminary analyses indicate that the temperature at the heat affected zone increases with the rotating speed.


2020 ◽  
Vol 67 (4) ◽  
pp. 345-355
Author(s):  
Suganeswaran Kandasamy ◽  
Parameshwaran Rathinasamy ◽  
Nithyavathy Nagarajan ◽  
Karthik Arumugam ◽  
Rajasekar Rathanasamy ◽  
...  

Purpose This paper aims to overcome the corrosion in AA7075 by incorporating the dual-reinforcements like Al2O3 and SiC through friction stir processing (FSP). In recent days, an automotive monocoque structure undergoes corrosion because of changes in environmental conditions. Design/methodology/approach Surface hybrid composites (SHCs) of AA7075 with different weight ratios of Al2O3 and SiC were fabricated at a rotating speed of 1000 rpm, traveling speed of 56 mm/min and tool tilt angle of 2º with two passes. Surface regions were observed using optical microscopy, and the potentiodynamic corrosion test was performed under a 3.5 per cent NaCl environment at room temperature. Then, the surface morphology analysis of corroded samples and their structural properties were also investigated through scanning electron microscopy (SEM), X-ray diffraction (XRD) and electron dispersive spectroscopy (EDS). Findings Through FSP, an improved interface between the reinforced particles and the AA7075 base matrix was observed because of the severe plastic deformation. Potentiodynamic polarization tests confirmed that the AA7075 matrix with a higher concentration of Al2O3 and a lower concentration of SiC (Al2O3 – 75 per cent and SiC – 25 per cent) possesses a lower corrosion rate than other specimens. This result is because of the combined effect of stable passive film formation and the resistance produced by hard SiC particles. In addition, the formation of a stronger interface between the reinforcements and the base matrix impedes the NaCl solution attack. The SEM micrograph depicts the film crystallinity variations with an increase in Al2O3 content. Debonding between the layers was observed on increasing the SiC content in the base matrix. XRD shows the peaks of reinforcing elements that influence the corrosion behavior. These observations suggest that the AA7075 reinforced with a higher concentration of Al2O3 and a lower concentration of SiC through FSP affords a suitable solution for automotive monocoque applications. Originality/value The corrosion rate has been identified for AA7075 SHCs with various concentrations of Al2O3 and SiC and has been compared with that of the base metal and the friction stir processed specimen without reinforcement.


2013 ◽  
Vol 372 ◽  
pp. 471-477
Author(s):  
Prapas Muangjunburee ◽  
Sirikul Wisutmethangoon

The effect of welding speeds and tool pin profiles on microstructure and mechanical properties of semi-solid metal 356 joints produced by friction stir welding was investigated. In this work, the joints were made by using a fixed rotating speed of 1750 rpm with varying welding speed of 80, 120 and 160 mm/min. In addition, two different types of tool pins, cylindrical and square pin, were applied. The Scanning Electron Microscope (SEM) reveals fine microstructure and uniform dispersion of Si (Silicon) particles obtained from cylindrical pin than that of square pin. Transverse and longitudinal tensile strengths obtained from cylindrical pin are greater than square pin. Furthermore, the joint made from 1750 rpm, 160 mm/min with cylindrical pin shows highest strength.


Author(s):  
Xun Liu ◽  
Sheng Zhao ◽  
Kai Chen ◽  
Jun Ni

In this study, the friction stir welding (FSW) of aluminum alloy 6061-T6511 to TRIP 780 steel is analyzed under various process conditions. Two FSW tools with different sizes are used. To understand the underlying joining mechanisms and material flow behavior, nano-computed tomography (nano-CT) is applied for a 3D visualization of material distribution in the weld. With insufficient heat input, steel fragments are generally scattered in the weld zone in large pieces. This is observed in a combined condition of big tool, small tool offset, and low rotating speed or a small tool with low rotating speed. Higher heat input improves the material flowability and generates a continuous strip of steel. The remaining steel fragments are much finer. When the volume fraction of steel involved in the stirring nugget is small, this steel strip can be in a flat shape near the bottom, which generally corresponds to a better joint quality and the joint would fracture in the base aluminum side. Otherwise, a hook structure is formed and reduces the joint strength. The joint would fail with a combined brittle behavior on the steel hook and a ductile behavior in the surrounding aluminum matrix.


Author(s):  
Eiji Ishii ◽  
Toru Ishikawa ◽  
Yoshiyuki Tanabe

To simulate multi-scale free surfaces, we developed a hybrid particle/grid method by which the free surfaces within sub-grid regions are simulated by the particle method, and other regions are simulated with the grid method. The particle method uses two types of particles to model gas and liquid fluids in order to simulate the interaction between them. We tested the new method on fragmentation of a water column, and the predicted configurations of the water column are consistent with measurements of Koshizuka and Oka. We also simulated the fuel spray near the outlet of an automobile-engine fuel injector and found that this method qualitatively simulated the breakup of the liquid film.


2013 ◽  
Vol 753-755 ◽  
pp. 431-434 ◽  
Author(s):  
Pierpaolo Carlone ◽  
Gaetano S. Palazzo

In recent years friction stir welding process has received a great deal of attention from the transport industry. During the process, heat generation and material stirring induce significant microstructural alteration in the base material, affecting the properties of the welded assembly. In this paper the influence of process parameters, namely rotating speed and welding speed, on mechanical properties of AA2024-T3 friction stir butt welds is experimentally investigated. An increase of the yield stress has been found decreasing the heat input, while an opposite variation was measured for the elongation.


Sign in / Sign up

Export Citation Format

Share Document