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 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.

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 Evaluation of Welding Residual Stresses Using Diffraction Spot Trace Method

2014 ◽  
Vol 996 ◽  
pp. 76-81
Author(s):  
Kenji Suzuki ◽  
Takahisa Shobu ◽  
Ayumi Shiro ◽  
Shuo Yuan Zhang
Keyword(s):  
Residual Stress ◽  
Residual Stresses ◽  
High Energy ◽  
Counting Efficiency ◽  
Diffraction Spot ◽  
Internal Stresses ◽  
X Rays ◽  
Area Detector ◽  
Coarse Grains ◽  
Slit System

A diffraction spot trace method (DSTM) is very useful to measure internal stresses of materials with coarse grains. In this study, validity of the DSTM was examined using high energy synchrotron X-ray of 70 keV. The specimen was a welded plate of austenitic stainless steel (SUS316L). The thickness of the specimen was 9 mm. The improved spiral slit system was used, and PILATUS was used as an area detector. It was difficult to detect the high energy X-rays due to the reduction of counting efficiency of the PILATUS. However, the residual stress map of the welding specimen was obtained by long exposure time. The residual stresses of the welding specimen were simulated by a finite element method (FEM). The outline of the residual stress measured by the DSTM coincided with that by the FEM.

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.

scholarly journals Mechanical and Microstructural Characterization of Friction Stir Welded SiC and B4C Reinforced Aluminium Alloy AA6061 Metal Matrix Composites

Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 3110
Author(s):  
Kaveripakkam Suban Ashraff Ali ◽  
Vinayagam Mohanavel ◽  
Subbiah Arungalai Vendan ◽  
Manickam Ravichandran ◽  
Anshul Yadav ◽  
...  
Keyword(s):  
Wear Rate ◽  
Aluminium Alloy ◽  
Metal Matrix Composites ◽  
Metal Matrix ◽  
Weld Zone ◽  
Base Material ◽  
Matrix Composites ◽  
Wear Properties ◽  
Friction Stir ◽  
Behavioural Aspects

This study focuses on the properties and process parameters dictating behavioural aspects of friction stir welded Aluminium Alloy AA6061 metal matrix composites reinforced with varying percentages of SiC and B4C. The joint properties in terms of mechanical strength, microstructural integrity and quality were examined. The weld reveals grain refinement and uniform distribution of reinforced particles in the joint region leading to improved strength compared to other joints of varying base material compositions. The tensile properties of the friction stir welded Al-MMCs improved after reinforcement with SiC and B4C. The maximum ultimate tensile stress was around 172.8 ± 1.9 MPa for composite with 10% SiC and 3% B4C reinforcement. The percentage elongation decreased as the percentage of SiC decreases and B4C increases. The hardness of the Al-MMCs improved considerably by adding reinforcement and subsequent thermal action during the FSW process, indicating an optimal increase as it eliminates brittleness. It was seen that higher SiC content contributes to higher strength, improved wear properties and hardness. The wear rate was as high as 12 ± 0.9 g/s for 10% SiC reinforcement and 30 N load. The wear rate reduced for lower values of load and increased with B4C reinforcement. The microstructural examination at the joints reveals the flow of plasticized metal from advancing to the retreating side. The formation of onion rings in the weld zone was due to the cylindrical FSW rotating tool material impression during the stirring action. Alterations in chemical properties are negligible, thereby retaining the original characteristics of the materials post welding. No major cracks or pores were observed during the non-destructive testing process that established good quality of the weld. The results are indicated improvement in mechanical and microstructural properties of the weld.

3-Dimensional Characterization of Polycrystalline Bulk Materials Using High-Energy Synchrotron Radiation

2007 ◽  
Vol 539-543 ◽  
pp. 2353-2358 ◽  
Author(s):  
Ulrich Lienert ◽  
Jonathan Almer ◽  
Bo Jakobsen ◽  
Wolfgang Pantleon ◽  
Henning Friis Poulsen ◽  
...  
Keyword(s):  
High Resolution ◽  
Synchrotron Radiation ◽  
High Energy ◽  
Mapping Technique ◽  
X Ray Diffraction ◽  
Bulk Materials ◽  
Reciprocal Space Mapping ◽  
3 Dimensional ◽  
Individual Grains

The implementation of 3-Dimensional X-Ray Diffraction (3DXRD) Microscopy at the Advanced Photon Source is described. The technique enables the non-destructive structural characterization of polycrystalline bulk materials and is therefore suitable for in situ studies during thermo-mechanical processing. High energy synchrotron radiation and area detectors are employed. First, a forward modeling approach for the reconstruction of grain boundaries from high resolution diffraction images is described. Second, a high resolution reciprocal space mapping technique of individual grains is presented.

Friction Stir Welding of Dissimilar Formed Mg Alloys (AZ31/AZ91)

2005 ◽  
Vol 486-487 ◽  
pp. 249-252 ◽  
Author(s):  
Chang Yong Lee ◽  
Won Bae Lee ◽  
Yun Mo Yeon ◽  
Seung Boo Jung
Keyword(s):  
Friction Stir Welding ◽  
Dynamic Recrystallization ◽  
Tensile Test ◽  
Intermetallic Compounds ◽  
Grain Growth ◽  
Weld Zone ◽  
Mg Alloys ◽  
Mg Alloy ◽  
Friction Stir ◽  
Az31 Mg Alloy

Friction stir welding of dissimilar formed Mg alloys(AZ31/AZ91) was successfully carried out at the limited welding conditions. In a sound joint, SZ was mainly consisted of AZ31 Mg alloy which was located the retreating side. Dynamic recrystallization and grain growth occurred and β intermetallic compounds of AZ 91 Mg alloy was not observed in SZ. BM had a higher hardness than that of the weld zone. The fracture location was not weld zone but BM of the AZ91 Mg alloy in tensile test.

Epitaxial Ni nanoparticles on CaF2(001), (110) and (111) surfaces studied by three-dimensional RHEED, GIXD and GISAXS reciprocal-space mapping techniques

2017 ◽  
Vol 50 (3) ◽  
pp. 830-839 ◽  
Author(s):  
S. M. Suturin ◽  
V. V. Fedorov ◽  
A. M. Korovin ◽  
N. S. Sokolov ◽  
A. V. Nashchekin ◽  
...  
Keyword(s):  
Lattice Structure ◽  
Three Dimensional ◽  
Grazing Incidence ◽  
High Energy ◽  
Reciprocal Space ◽  
Mapping Technique ◽  
Face Centered Cubic ◽  
X Ray ◽  
Cubic Lattice ◽  
Face Centered

The development of growth techniques aimed at the fabrication of nanoscale heterostructures with layers of ferroic 3dmetals on semiconductor substrates is very important for their potential usage in magnetic media recording applications. A structural study is presented of single-crystal nickel island ensembles grown epitaxially on top of CaF2/Si insulator-on-semiconductor heteroepitaxial substrates with (111), (110) and (001) fluorite surface orientations. The CaF2buffer layer in the studied multilayer system prevents the formation of nickel silicide, guides the nucleation of nickel islands and serves as an insulating layer in a potential tunneling spin injection device. The present study, employing both direct-space and reciprocal-space techniques, is a continuation of earlier research on ferromagnetic 3dtransition metals grown epitaxially on non-magnetic and magnetically ordered fluorides. It is demonstrated that arrays of stand-alone faceted nickel islands with a face-centered cubic lattice can be grown controllably on CaF2surfaces of (111), (110) and (001) orientations. The proposed two-stage nickel growth technique employs deposition of a thin seeding layer at low temperature followed by formation of the islands at high temperature. The application of an advanced three-dimensional mapping technique exploiting reflection high-energy electron diffraction (RHEED) has proved that the nickel islands tend to inherit the lattice orientation of the underlying fluorite layer, though they exhibit a certain amount of {111} twinning. As shown by scanning electron microscopy, grazing-incidence X-ray diffraction (GIXD) and grazing-incidence small-angle X-ray scattering (GISAXS), the islands are of similar shape, being faceted with {111} and {100} planes. The results obtained are compared with those from earlier studies of Co/CaF2epitaxial nanoparticles, with special attention paid to the peculiarities related to the differences in lattice structure of the deposited metals: the dual-phase hexagonal close-packed/face-centered cubic lattice structure of cobalt as opposed to the single-phase face-centered cubic lattice structure of nickel.

scholarly journals Influence of Mx-Trivex, A-Skew, Three Flat Threaded and Concave Shouldered Mx-Triflute Tool Pin Profiles on Tensile Properties and Fractural Behaviour of Aa 6082-T6 Weldments During Friction Stir Welding

2020 ◽  
Vol 9 (4) ◽  
pp. 1376-1384
Keyword(s):  
Friction Stir Welding ◽  
Tensile Test ◽  
Weld Zone ◽  
Base Material ◽  
Traverse Speed ◽  
Friction Stir ◽  
Tool Pin ◽  
Solid State Joining ◽  
Joining Process ◽  
Brass Wire

Friction Stir Welding (FSW) is a topical and propitious solid-state joining process producing economical and strengthened joints of age-hardened and heat-treatable Aluminium Alloy AA 6082-T6. Mechanical and fractural behaviour of weldments were investigated in order to find crack initiation and necking on the weld zone thereby perceiving the complete behaviour of fracture occurred near the weld zone. Weldments are fabricated by employing four tool pin profiles namely MX-TRIVEX, A-SKEW, Three flat threaded and Concave shouldered MX-TRIFLUTE tools at various rotational speeds 1000 rpm, 1200 rpm and 1400 rpm at single traverse speed 25 mm/min. EXCETEX-EX-40 CNC wire cut EDM with 0.25 mm brass wire diameter has been employed to perform the extraction of tensile test specimens from the weldments according to ASTM E8M-04 standard. Tensile test was performed on elctromechanically servo controlled TUE-C-200 (UTM machine) according to ASTM B557-16 standards Maximum Ultimate Tensile Strength (UTS) of 172.33 MPa (55.5% of base material) and 0.2% Yield Stress (YS) of 134.10 MPa (51.5% of base material) were obtained by using A-SKEW at 1400 rpm, 25 mm/min and maximum % Elongation (%El) of 11.33 (113.3% of base material) was obtained at MX-TRIVEX at 1000 rpm, 25 mm/min. Minimum UTS of 131.16 MPa (42.30% of base material) and 0.2% YS of 105.207 MPa (40.46% of base material )were obtained by using Concave shouldered MX-TRIFLUTE at 1400 rpm, 25 mm/min. Minimum % El of 5.42 ( 54.2% of base material) was obtained by using A-SKEW at 1000 rpm, 25 mm/min.

Sign in / Sign up

Export Citation Format

Share Document