scholarly journals Depth Resolved Strain and Phase Mapping of Dissimilar Friction Stir Welds Using High Energy Synchrotron Radiation

2003 ◽  
Vol 35 (3-4) ◽  
pp. 145-152 ◽  
Author(s):  
R. V. Martins ◽  
V. Honkimäki
Keyword(s):  
Longitudinal Strain ◽  
Phase Distribution ◽  
Weld Zone ◽  
High Energy ◽  
Friction Stir Weld ◽  
Mapping Technique ◽  
Strain Component ◽  
Strain Mapping ◽  
Friction Stir ◽  
Phase Mapping

The strain and phase distribution in a dissimilar friction stir weld of AA6082-T6 to AA2024-T3 is investigated non-destructively. The measurements are performed using a novel depth resolved strain and phase mapping technique. The technique is based on the use of a focussed high energy synchrotron beam, a novel spiral slit system, and an area detector system. Through thickness measurements of the residual strain along the weld centre show strong variations with changes of sign. The strain scans across the weld exhibit a strong asymmetry in particular for the longitudinal strain component. A depth resolved strain mapping across the weld shows for the dominant longitudinal strain component variations in depth, especially on the AA6082 side of the weld. Results from the strain measurements are related to the depth resolved map of the material distribution in the weld zone.

Depth Resolved Investigation of Friction Stir Welds Made from AA2024 / AA2024 and AA2024 / AA6082 Using a Spiral Slit and High Energy Synchrotron Radiation

2005 ◽  
Vol 490-491 ◽  
pp. 424-429 ◽  
Author(s):  
René V. Martins ◽  
Veijo Honkimäki
Keyword(s):  
Longitudinal Strain ◽  
Weld Zone ◽  
High Energy ◽  
Mapping Technique ◽  
Strain Component ◽  
Strain Mapping ◽  
Friction Stir ◽  
Dissimilar Weld ◽  
Area Detector ◽  
Slit System

The strain and phase distributions in friction stir welds (FSW) of AA2024-T3 to AA2024-T3 and AA2024-T3 to AA6082-T6 are investigated non-destructively. The measurements are performed using a novel depth resolved strain and phase mapping technique. The technique is based on the use of a focussed high energy synchrotron beam, a novel spiral slit system, and an area detector system. The strain scans across the dissimilar FSW exhibit a strong asymmetry in particular for the longitudinal strain component. A depth resolved strain mapping across the weld shows for the dominant longitudinal strain component variations in depth, especially on the AA6082 side of the dissimilar weld. The variations are significantlty weaker in the AA2024 / AA2024 weld. Results from the strain measurements are related to the depth resolved map of the material distribution in the weld zone.

scholarly journals Parametric Optimization of Friction Stir Welding Factors (FSWF) for Yellow Brass 405-20

2021 ◽  
Author(s):  
Syed Farhan Raza ◽  
Sarmad Ali Khan ◽  
Muhammad Salman Habib ◽  
Naveed Ahmed ◽  
Kashif Ishfaq ◽  
...  
Keyword(s):  
Friction Stir Welding ◽  
Rotational Speed ◽  
Weld Zone ◽  
Tool Material ◽  
Traverse Speed ◽  
Weld Strength ◽  
Friction Stir Weld ◽  
Friction Stir ◽  
Wide Range ◽  
Percent Contribution

Abstract Friction stir welding (FSW) is a green, environmentally amicable, and solid-state joining technology. Industries are really interested in adopting FSW in its various applications e.g., automobile, aerospace, marine, construction, etc. FSW can successfully weld a wide range of materials (similar/dissimilar parent materials) including aluminum, copper, steel, different alloys from these materials, plastics, composites, and this material range is subjected to extension if FSW research efforts develop further in future. FSW of brass has already been accomplished by fewer researchers. In this research, yellow brass 405-20 is, therefore, welded with FSW that was never welded before. In this study, tool material utilized was M2 HSS that was also novel. Effect of two friction stir weld factors (FSWF), rotational speed (RS) and traverse speed (TS), was found on three output parameters i.e., weld temperature, weld strength and weld hardness. Weld temperature was found to be 63.72% of melting point of base metal. A significant improvement in friction stir weld strength (FSWS) was also measured that was found to be 82.78% of the base brass strength. Finally, weld hardness was measured which was found to be 87.80% of original brass hardness. Based on main effects of Anova Analysis, optimal FSW factors were found to be 1450 rpm and 60 mm/min resulting interestingly in maximum (max.)/optimal temperature, max./optimal weld strength, and minimum/optimal hardness. Rotational speed (RS) was found to be significant to affect the weld temperature only at the friction stir weld zone (FSWZ) with the highest percent contribution (PCR) of 65.69%. Transverse speed (TS) was found to be overall insignificant for affecting weld temperature, weld strength and hardness. However, PCR of transverse speed was found to be maximum for affecting weld strength as compared to its PCR towards both weld temperature and weld hardness. Error PCR was found to be the lowest for weld zone temperature, then for weld strength, and finally the highest for weld hardness. Interaction Plots (IPs) were also made for those FSWF which were found to be insignificant and to investigate any combined effect of FSWF on output parameters causing increased error PCR towards weld temperature, weld strength, and weld hardness.

Friction Stir Welding of Carbon Steel for Application in Used Fuel Containers

2014 ◽  
Vol 783-786 ◽  
pp. 1753-1758 ◽  
Author(s):  
Murray Mahoney ◽  
Sam Sanderson ◽  
Peter Maak ◽  
Russell Steel ◽  
Jon Babb ◽  
...  
Keyword(s):  
Friction Stir Welding ◽  
Room Temperature ◽  
Steel Plate ◽  
Ultrasonic Inspection ◽  
Weld Zone ◽  
Friction Stir Weld ◽  
Weld Repair ◽  
Friction Stir ◽  
Flat Steel ◽  
Two Phases

Friction Stir Welding (FSW) is being investigated as a method to fabricate a partial penetration closure weld of the steel vessel of a copper-coated used fuel container. The hemi-head is made of A516 Grade 70 steel and the cylinder body is made of A106 Grade C steel. In this initial feasibility study, the objective is to use FSW to demonstrate the merits of FSW using flat steel plate in concert with a closure weld joint designed specifically for a cylindrical container. To complete this objective, there are two initial feasibility demonstrations. First, demonstrate the capability of FSW to create defect free welds in a corner joint design with specific dimensions (10 mm deep weld nugget). Subsequently, verify the weld quality by ultrasonic inspection and metallography. Further, characterize weld zone properties by establishing mechanical properties and hardness at room temperature, and impact toughness at-5°C. Second, demonstrate the ability to use FSW to repair defects that might occur in the initial friction stir weld. Weld repair was accomplished by intentionally creating tunnel defects by FSW, performing metallography and ultrasonic inspection to characterize the morphology of the defects, performing a second friction stir weld repair over the defects, and verifying the subsequent weld integrity by repeating the metallography and ultrasonic inspections. Results on these initial two phases of this program are presented herein.

scholarly journals Repair Welding of the Tunnel Defect in Friction Stir Weld

2018 ◽  
Vol 37 (7) ◽  
pp. 675-681 ◽  
Author(s):  
Weipo Li ◽  
Zhimin Liang ◽  
Congwei Cai ◽  
Dianlong Wang
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Yield Strength ◽  
Weld Zone ◽  
Welding Process ◽  
Friction Stir Weld ◽  
Strength Increase ◽  
Repair Welding ◽  
Friction Stir ◽  
Longitudinal Residual Stress

AbstractThe tunnel defect formed in friction stir weld would dramatically push the mechanical properties of joints into deterioration. In this study, friction stir welding process was adopted to repair the joints of 7N01 aluminum alloy with tunnel defect. The effects of friction stir repair welding process on the microstructure and mechanical properties were comprehensively investigated. Microstructure of the repaired joints shows that the grain size in nugget zone decreases slightly while the recrystallization in the retreating side of thermo-mechanically affected zone is intensified as the joints are repaired. The microhardness of the repaired joints declined slightly compared with the defective joint. However, the yield strength and tensile strength increase and recover to the values of the joints free of defect. The longitudinal residual stress in weld zone increased remarkably as the repair times increase. Compared with the once repaired joint, yield strength and tensile strength of the twice repaired joint reduced slightly, and the throat thickness also reduced during the repeated repair welding process. Therefore, the times of repair welding applied should be limited actually.

Synchrotron Energy-Dispersive X-Ray Diffraction Analysis of Residual Strains around Friction Welds between Dissimilar Aluminium and Nickel Alloys

2008 ◽  
Vol 571-572 ◽  
pp. 407-412 ◽  
Author(s):  
Tea Sung Jun ◽  
Shu Yan Zhang ◽  
Mina Golshan ◽  
Matthew J. Peel ◽  
David G. Richards ◽  
...  
Keyword(s):  
Friction Welding ◽  
Nickel Alloys ◽  
Dissimilar Materials ◽  
High Energy ◽  
Bond Line ◽  
Energy Dispersive ◽  
Mapping Technique ◽  
Friction Stir ◽  
Residual Strains ◽  
Welding Processes

Friction welding processes, such as friction stir welding (FSW) and inertia friction welding (IFW) are popular candidate procedures for joining engineering materials (including dissimilar pairs) for advanced applications. The advantages of friction welding include lack of large scale material melting, ability to join dissimilar materials, and relatively low propensity to introduce defects into the weld joint. For these reasons FSW and IFW have become the subjects of a number of studies aimed at optimising the joining operations to obtain improved joint strength and reduce distortion and residual stress. In the present study we used the diffraction of high energy polychromatic synchrotron X-rays to measure interplanar lattice spacings and deduce nominal elastic strains in friction stir welds between dissimilar aluminium alloys AA5083 and AA6082, and in coupons from inertia friction welds between dissimilar nickel-base superalloys IN718 and RR1000. Energy-dispersive diffraction profiles were collected by two detectors mounted in the horizontal and vertical diffraction planes, providing information about lattice strains in two nearly perpendicular directions lying almost in the plane of the plate samples mounted perpendicularly to the incident beam. Two-dimensional maps of residual stresses in friction-welded joints were constructed. Apart from the 2D mapping technique, the sin2ψ method (transmission) was also used in the case of inertia friction-welded joint between nickel alloys. Comparison between the two results allowed the variation of the lattice parameter with the distance from the bond line to be deduced. It was found that friction welding of two dissimilar materials with significant strength mismatch may lead to the creation of a region of compressive stress in the vicinity of the bond line, in contrast with the behaviour observed for joints between similar materials.

scholarly journals IMPROVED CORROSION RESISTANCE OF FRICTION STIR ZONE OF RARE EARTH MAGNESIUM ALLOY AE42

2013 ◽  
pp. 21-24
Author(s):  
M GOVINDARAJU ◽  
K BALASUBRAMANIAN ◽  
K PRASAD RAO ◽  
UDAY CHAKKINGAL
Keyword(s):  
Corrosion Resistance ◽  
Magnesium Alloy ◽  
Weld Zone ◽  
Friction Stir Weld ◽  
Second Phase ◽  
Uniform Corrosion ◽  
Parent Metal ◽  
Electron Microscopic ◽  
Experimental Conditions ◽  
Friction Stir

Corrosion studies on friction stir welded AE42 magnesium alloy were carried out in 0.1 M ammonium carbonate solution. For better understanding, comparative analysis of corrosion rates was carried out before and after welding. Friction stir weld zone was more corrosion resistant than the parent metal under similar experimental conditions. Grain size was refined at weld zone. Second phase intermetallic particles were refined into tiny pieces of 1-2 micron size and evenly distributed throughout the matrix. Local electrochemical imbalance was eliminated due to the grain refinement and elimination of continuous grain boundary. These phenomena improved the corrosion resistance of weld zone. Scanning electron microscopic images confirmed mild and uniform corrosion of weld zone and rigorous inhomogeneous corrosion of parent metal.

Zone Wise Properties of Friction Stir Welded Copper – Stainless Steel Joints Using Digital Image Correlation

2015 ◽  
Vol 787 ◽  
pp. 485-489 ◽  
Author(s):  
Karthik Srinivas ◽  
R. Saranarayanan ◽  
A.K. Lakshminarayanan ◽  
N. Srinivasan ◽  
B. Venkatraman
Keyword(s):  
Stainless Steel ◽  
Digital Image Correlation ◽  
Digital Image ◽  
Tensile Deformation ◽  
Weld Zone ◽  
Image Correlation ◽  
Friction Stir Weld ◽  
Uniaxial Tensile ◽  
Theoretical Understanding ◽  
Friction Stir

Recent developments in imaging non destructive evaluation techniques offer possibilities of quantitative measurement of strain localizations associated with plastic instabilities. Digital image correlation is a technique now being widely employed for studying the temporal strain evolution associated during tensile deformation. This work focuses on the application of digital image correlation to visualise the two dimensional strain evolutions in the weld zone, heat affected zone and the base metal during monotonic uniaxial tensile deformation of friction stir weld samples of copper – stainless steel. The results indicated that the Cu- Stainless steel weld interface exhibited a lower tensile strength compared to the other regions. The experimental observations are discussed in relation with the current theoretical understanding. The experiments also reveal the potential of advanced imaging NDE methods for providing better insights of the micro mechanisms of deformation and failure including local deformation characteristics of the material under study.

scholarly journals An Evaluation of Optimal Friction Stir Welding Factors (FSWF) For Yellow Brass 405-20

2022 ◽  
Author(s):  
Syed Farhan Raza ◽  
Sarmad Ali Khan ◽  
Muhammad Salman Habib ◽  
Naveed Ahmed ◽  
Kashif Ishfaq ◽  
...  
Keyword(s):  
Friction Stir Welding ◽  
Rotational Speed ◽  
Weld Zone ◽  
Tool Material ◽  
Traverse Speed ◽  
Microscopic Investigation ◽  
Weld Strength ◽  
Friction Stir Weld ◽  
Friction Stir ◽  
Wide Range

Abstract Friction stir welding (FSW) is a green, environmentally amicable, and solid-state joining technology. FSW can successfully weld a wide range of materials (similar/dissimilar parent materials) including aluminum, copper, steel, different alloys from these materials, plastics, composites. FSW of brass has already been accomplished by fewer researchers. In this research, yellow brass 405-20 is, therefore, welded with FSW that was never welded before. In this study, tool material utilized was M2 HSS that was also novel. Effect of two friction stir weld factors (FSWF), rotational speed (RS) and traverse speed (TS), was found on three output parameters i.e., weld temperature, weld strength and weld hardness. Weld temperature developed, was found to be 63.72% of melting point of base metal. A significant improvement in friction stir weld strength (FSWS) was also measured that was found to be 106.37% of the base brass strength. Finally, weld hardness was measured which was found to be 87.80% of original brass hardness. Based on main effects, optimal FSW factors were found to be 1450 rpm and 60 mm/min resulting interestingly in optimal temperature, optimal weld strength, and optimal hardness. Rotational speed (RS) was found to be significant to affect the weld temperature only at the friction stir weld zone (FSWZ) with the highest percent contribution (PCR) of 65.69%. However, PCR of transverse speed was found to be maximum for affecting weld strength as compared to its PCR towards both weld temperature and weld hardness. Current study was also deepened by microscopic investigation.

Effects of bottom plate in friction stir welding of AA6061-T6

2020 ◽  
Vol 118 (1) ◽  
pp. 108
Author(s):  
M.A. Vinayagamoorthi ◽  
M. Prince ◽  
S. Balasubramanian
Keyword(s):  
Mechanical Properties ◽  
Axial Load ◽  
Weld Zone ◽  
Welding Process ◽  
Bottom Plate ◽  
Welding Parameters ◽  
Nugget Zone ◽  
Friction Stir ◽  
Weld Joints ◽  
Fine Grain

The effects of 40 mm width bottom plates on the microstructural modifications and the mechanical properties of a 6 mm thick FSW AA6061-T6 joint have been investigated. The bottom plates are placed partially at the weld zone to absorb and dissipate heat during the welding process. An axial load of 5 to 7 kN, a rotational speed of 500 rpm, and a welding speed of 50 mm/min are employed as welding parameters. The size of the nugget zone (NZ) and heat-affected zone (HAZ) in the weld joints obtained from AISI 1040 steel bottom plate is more significant than that of weld joints obtained using copper bottom plate due to lower thermal conductivity of steel. Also, the weld joints obtained using copper bottom plate have fine grain microstructure due to the dynamic recrystallization. The friction stir welded joints obtained with copper bottom plate have exhibited higher ductility of 8.9% and higher tensile strength of 172 MPa as compared to the joints obtained using a steel bottom plate.

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