Neutron Diffraction Measurements on Dissimilar Metal Weld of Cu-Al Obtained by Friction Stir Welding Method

Dissimilar metal weld (DMW) of Cu and Al alloy, namely DMW CuAl, was produced using Friction Stir Welding (FSW) technique. Characterization was performed at retreating and advancing side by neutron diffraction method. It is obtained that the weight percent composition of Cu and Al are dynamically change, depend on weld zone and welding direction. In SZ Cu element 55,18%, and it is majority component in the retreating side and it decreases gradually from the retreating side to the advancing side. The weight percent composition of Cu in the retreating side at HAZ and TMAZ are 99.25 %, and 61.25%, respectively, and in the advancing side are 0.35% and 38.75 %, respectively. Cu Bragg peaks of (111), (200) and (220) show that peak width ratio of BMZ / SZ is approximately 13%. This indicates a change in crystallite size that affects the behavior of plastic deformation in the welded material.

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Experimental Characterisation and Numerical Modelling of Residual Stresses in a Nuclear Safe-End Dissimilar Metal Weld Joint

Metals ◽

10.3390/met11081298 ◽

2021 ◽

Vol 11 (8) ◽

pp. 1298

Author(s):

Shuyan Zhang ◽

Zhuozhi Fan ◽

Jun Li ◽

Shuwen Wen ◽

Sanjooram Paddea ◽

...

Keyword(s):

Residual Stress ◽

Neutron Diffraction ◽

Residual Stresses ◽

Weld Joint ◽

Steel Tube ◽

Contour Method ◽

Fe Modelling ◽

Dissimilar Metal ◽

Dissimilar Metal Weld ◽

Metal Weld

In this study, a mock-up of a nuclear safe-end dissimilar metal weld (DMW) joint (SA508-3/316L) was manufactured. The manufacturing process involved cladding and buttering of the ferritic steel tube (SA508-3). It was then subjected to a stress relief heat treatment before being girth welded together with the stainless steel tube (316L). The finished mock-up was subsequently machined to its final dimension. The weld residual stresses were thoroughly characterised using neutron diffraction and the contour method. A detailed finite element (FE) modelling exercise was also carried out for the prediction of the weld residual stresses resulting from the manufacturing processes of the DMW joint. Both the experimental and numerical results showed high levels of tensile residual stresses predominantly in the hoop direction of the weld joint in its final machined condition, tending towards the OD surface. The maximum hoop residual stress determined by the contour method was 500 MPa, which compared very well with the FE prediction of 467.7 Mpa. Along the neutron scan line at the OD subsurface across the weld joint, both the contour method and the FE modelling gave maximum hoop residual stress near the weld fusion line on the 316L side at 388.2 and 453.2 Mpa respectively, whereas the neutron diffraction measured a similar value of 480.6 Mpa in the buttering zone near the SA508-3 side. The results of this research thus demonstrated the reasonable consistency of the three techniques employed in revealing the level and distribution of the residual stresses in the DMW joint for nuclear applications.

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Study of friction stir welding between AZ31 Mg alloy and 6061 Al alloy joint using neutron diffraction

10.1063/5.0066930 ◽

2021 ◽

Author(s):

K. Rina ◽

I. Andon ◽

M. Herry ◽

S. Muhammad ◽

P. M. A. Muzakkiy ◽

...

Keyword(s):

Friction Stir Welding ◽

Neutron Diffraction ◽

Mg Alloy ◽

Al Alloy ◽

Friction Stir ◽

Az31 Mg Alloy ◽

6061 Al Alloy

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Effect of PWHT on Behaviors of Precipitates and Hardness Distribution of 6061 Al Alloy Joints by Friction Stir Welding Method

Materials Science Forum ◽

10.4028/www.scientific.net/msf.449-452.601 ◽

2004 ◽

Vol 449-452 ◽

pp. 601-604 ◽

Cited By ~ 3

Author(s):

Won Bae Lee ◽

Hyung Sun Jang ◽

Yun Mo Yeon ◽

Seung Boo Jung

Keyword(s):

Friction Stir Welding ◽

Base Metal ◽

Dynamic Recovery ◽

Weld Zone ◽

Frictional Heat ◽

Al Alloy ◽

Hardness Distribution ◽

Friction Stir ◽

Heat Treated ◽

6061 Al Alloy

The hardness distribution related to the precipitates behaviors as friction stir welded and PWHT (post weld heat treated) 6061 Al alloy have been investigated. Frictional heat and plastic flow during friction stir welding created a fine, eqiuaxed and elongated microstructure near the weld zone due to dynamic recovery and recrystallization. A softened region which had been formed near the weld zone couldn't be avoidable due to the dissolution and coarsening of the strengthening precipitates. PWHT (SHT+ Aging) homogeneously recovered the hardness distribution over that of the base metal without softening region, resulted from non-homogeneously distributed hardness only aging treated. 36ks aging followed by SHT gave a higher hardness overall weld than that of the base metal due to a higher density of the spherical shaped precipitate.;

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Temperature Based Optimization of Friction Stir Welding of AA 6061 Using GRA Synchronous With Taguchi Method

10.21203/rs.3.rs-841292/v1 ◽

2021 ◽

Author(s):

Eyob Messele ◽

Assefa Asmare Tsegaw

Keyword(s):

Friction Stir Welding ◽

Base Metal ◽

Weld Zone ◽

Welding Process ◽

Quality Characteristic ◽

Heat Transfer Analysis ◽

Al Alloy ◽

Welding Temperature ◽

Friction Stir ◽

Tool Pin

Abstract One of the recent novel joining mechanisms in the solid-state-welding process is Friction Stir Welding (FSW). The process is extensively used in joining similar and dissimilar materials as well. This research studied and found the optimum process parameters of FSW based on the temperature simulation results on a 5 mm 6061 Al alloy sheet with a butt joint configuration. Steady-state heat transfer analysis was performed using a transient thermal workbench to predict and identify the optimum parameters grounded on the simulation welding temperature result. The parameters are optimized using the hybrid Taguchi L9 orthogonal array and Grey relation analysis method with a larger is better quality characteristic. Mechanical properties of the weld joints' such as hardness and tensile strength, were studied at an ambient temperature. The result revealed that a higher rotational speed with a minimum traverse speed and taper threaded tool pin impart the optimum parameter settings. Analysis of variance (ANOVA) was carried out also to determine the effects of each process parameter. At a 95 % confidence interval, rotational and traverse speeds show significant characteristics. The joint efficiency reached 92.25% of the base metal at a maximum welding temperature. Additionally, the microstructure of the stir weld zone of the specimen was studied as well. Metallographic Characterization carried out using Scanning Electron Microscope (SEM) revealed the microstructure of the samples after the weld did not show any significant change with the base metal. Furthermore, this study scheme can be extended to thick non-ferrous, ferrous, and metal-based composite materials, too.

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Formation of Unmixed Zone in the Fusion Boundary of Dissimilar Metal Weld Zone

Journal of Welding and Joining ◽

10.5781/kwjs.2007.25.4.001 ◽

2007 ◽

Vol 25 (4) ◽

pp. 1-3 ◽

Cited By ~ 1

Author(s):

Chang-Hee Lee

Keyword(s):

Weld Zone ◽

Fusion Boundary ◽

Dissimilar Metal ◽

Dissimilar Metal Weld ◽

Metal Weld

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Residual Stress Analysis in a Thick Dissimilar Metal Weld Based on Neutron Diffraction

Residual Stress, Fracture, and Stress Corrosion Cracking ◽

10.1115/pvp2004-2651 ◽

2004 ◽

Cited By ~ 8

Author(s):

Carsten Ohms ◽

Dimitrios E. Katsareas ◽

Robert C. Wimpory ◽

Peter Hornak ◽

Anastasius G. Youtsos

Keyword(s):

Residual Stress ◽

Neutron Diffraction ◽

Residual Stresses ◽

Stress Analysis ◽

Test Procedure ◽

Diffraction Method ◽

Research Centre ◽

Dissimilar Metal ◽

Dissimilar Metal Weld ◽

Metal Weld

Residual stresses in welded structural components can significantly compromise their performance and lifetime. Non-destructive measurement of such stresses remains a challenging task and neutron diffraction, in principle similar to X-ray diffraction, is used in this study. At the High Flux Reactor (HFR) of the Joint Research Centre (JRC), Petten, the Netherlands, a facility is available to investigate residual stresses in components of up to 1000 kg — the Large Component Neutron Diffraction Facility (LCNDF). Residual stress measurements in a dissimilar metal weld are presented. The specimen investigated is a full-scale mock-up of a pressure vessel to primary piping bi-metallic weld. The specimen wall thickness is 51 mm. A key issue in applying neutron diffraction to welds is the reliable estimation of the stress-free lattice spacing in the heat affected zones and weld pool. The description of the test procedure and the resulting strain/stress data are presented in this paper. Based on this a predictive FEM model has been calibrated. Comparison of test data and numerical results clearly shows that the neutron diffraction method as applied at the HFR, although touching its limits in this study, is still capable of yielding 3-D stress analysis data in steel specimens of more than 50 mm thickness.

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The effect of pin probe length on the characteristic of dissimilar metal Al-CuZn lap joint using friction stir welding (FSW)

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/1034/1/012160 ◽

2021 ◽

Vol 1034 (1) ◽

pp. 012160

Author(s):

Widia Setiawan ◽

Muhammad Badarudin Thoha ◽

Surojo ◽

Nugroho Santoso

Keyword(s):

Friction Stir Welding ◽

Lap Joint ◽

Probe Length ◽

Friction Stir ◽

Dissimilar Metal

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Effect of Stirring Pin Rotation Speed on Microstructure and Mechanical Properties of 2A14-T4 Alloy T-Joints Produced by Stationary Shoulder Friction Stir Welding

Materials ◽

10.3390/ma14081938 ◽

2021 ◽

Vol 14 (8) ◽

pp. 1938

Author(s):

Haifeng Yang ◽

Hongyun Zhao ◽

Xinxin Xu ◽

Li Zhou ◽

Huihui Zhao ◽

...

Keyword(s):

Mechanical Properties ◽

Friction Stir Welding ◽

Rotation Speed ◽

Weld Nugget ◽

Al Alloy ◽

Nugget Zone ◽

T Joints ◽

Friction Stir ◽

Stationary Shoulder ◽

Microstructure And Mechanical Properties

In this study, 2A14-T4 Al-alloy T-joints were prepared via stationary shoulder friction stir welding (SSFSW) technology where the stirring pin’s rotation speed was set as different values. In combination with the numerical simulation results, the macro-forming, microstructure, and mechanical properties of the joints under different welding conditions were analyzed. The results show that the thermal cycle curves in the SSFSW process are featured by a steep climb and slow decreasing variation trends. As the stirring pin’s rotation speed increased, the grooves on the weld surface became more obvious. The base and rib plates exhibit W- or N-shaped hardness distribution patterns. The hardness of the weld nugget zone (WNZ) was high but was lower than that of the base material. The second weld’s annealing effect contributed to the precipitation and coarsening of the precipitated phase in the first weld nugget zone (WNZ1). The hardness of the heat affect zone (HAZ) in the vicinity of the thermo-mechanically affected zone (TMAZ) dropped to the minimum. As the stirring pin's rotation speed increased, the tensile strengths of the base and rib plates first increased and then dropped. The base and rib plates exhibited ductile and brittle/ductile fracture patterns, respectively.

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