Effect of Welding Parameters on Temperature Distribution During Friction Stir Spot Welding of Commercial Pure Copper Lap Joint

In this paper, a Coupled Eulerian Lagrangian (CEL) finite element model (FEM) was developed to simulate the friction stir spot welding (FSSW) of commercial pure copper. Through simulations results, the paper presents and discusses the effect of FSSW process parameters; namely rotational speed, plunging rate and dwell time, on the developed temperatures and their distribution within the workpiece as well as material flow and deformation. Model validation showed a good agreement between predicted temperature history and the experiment one, with a maximum error of 6%. Furthermore, the predicted formation of flash was also found in good agreement with the experiment with an error of only 7%. Simulation results predicted peak temperature and plastic strain among all studied welding conditions were 920 K and 3.5 respectively at 1200 rpm rotational speed, 20 mm/min plunging rate and 4 seconds dwell time, which is approximately 70% of the melting point of pure copper.

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Effect of Welding Conditions on Sheets’ Interface Properties in Friction Stir Spot Welding of Copper

Volume 6A: Materials and Fabrication ◽

10.1115/pvp2019-93635 ◽

2019 ◽

Author(s):

Ahmed Mahgoub ◽

Neçar Merah ◽

Abdelaziz Bazoune

Keyword(s):

Surface Morphology ◽

Rotational Speed ◽

Spot Welding ◽

Dwell Time ◽

Friction Stir Spot Welding ◽

Tensile Failure ◽

Welding Parameters ◽

Welding Condition ◽

Friction Stir ◽

Joint Fracture

Abstract Friction Stir Spot Welding (FSSW) is a solid-state joining technique widely applied to high conductive metals. In this paper, the effects of FSSW parameters, namely, rotational speed (N), plunging rate (V) and dwell time (DT) on the joint fracture mode and fractured surface morphology were investigated using scanning electron microscopy (SEM). The effect of the abovementioned welding parameters on the microhardness profile along the sheets’ interface was also investigated to gain insight into the strength of the joint and the width of the bonding ligament. Two conditions were considered for each parameter 1200 rpm and 900 rpm for N, 60 mm/min and 20 mm/min for V, 4 and 2 seconds for DT. The welding condition 1200 rpm rotational speed, 20 mm/min plunging rate and 2 seconds dwell time showed a wider bonding ligament, relatively higher elongation, higher tensile failure load, and greater microhardness on the sheets’ interface. Dimple surface morphology (DSM) with regular dimples along the stir zone was also observed at the abovementioned set of process parameters.

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Friction Stir Spot Welding of AZ31B Magnesium Alloy

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.867.105 ◽

2017 ◽

Vol 867 ◽

pp. 105-111

Author(s):

S. Ramesh Babu ◽

M. Nithin ◽

S. Pavithran ◽

B Parameshwaran

Keyword(s):

Shear Strength ◽

Magnesium Alloy ◽

Rotational Speed ◽

Spot Welding ◽

Dwell Time ◽

Friction Stir Spot Welding ◽

Resistance Welding ◽

Hardness Distribution ◽

Tool Rotational Speed ◽

Friction Stir

The Electrical Resistance Welding (ERW) of Magnesium and Aluminium is more difficult than steel because the welding machines must provide high currents and exact pressures in order to provide the heat necessary to melt the magnesium for proper fusion at the interface in order to produce a sound weld. Further, resistance welding of magnesium requires a backup plate made of steel to conduct the heat to the workpiece material. To overcome this problem, Friction Stir Spot Welding (FSSW) has been developed. In this study, the hardness distribution and the tensile shear strength of FSSW welds in the AZ31B Magnesium alloy has been investigated and it has been found that tool rotational speed and dwell time plays a major role in determining the weld strength. From the experimental study, a tool rotational speed of 1100 rpm and dwell time of 20 s produced good shear strength of 2824 N and the corresponding grain size was 4.54 μm. This result is very well supported by microstructural examinations and hardness distribution studies.

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Effects of process parameters on the lap joint strength and morphology in friction stir spot welding of ABS sheets

Journal of Elastomers & Plastics ◽

10.1177/0095244320961525 ◽

2020 ◽

pp. 009524432096152

Author(s):

Asil Ayaz ◽

Aydin Ülker

Keyword(s):

Spot Welding ◽

Dwell Time ◽

Joint Strength ◽

Friction Stir Spot Welding ◽

Welding Parameters ◽

Shear Load ◽

Lap Joint ◽

Friction Stir ◽

Joint Shear ◽

Tool Rotation

In this study, a new method was proposed to reduce the keyhole volume with friction stir spot welding process and improve the lap joint shear load-carrying capacity of the weld by analyzing the effects of tool rotation speed, plunge depth and dwell time on the weld. Single lap shear tests were carried out to determine the influences of the welding parameters on the mechanical behavior of the welds. The quality of the joint was evaluated by examining the characteristics of the joint as a result of the lap joint shear load. For friction stir spot welding of the acrylonitrile butadiene styrene samples, the experiments were designed according to Taguchi’s L9 orthogonal array in a randomized way. From the analysis of variance and the signal-to-noise ratio, the significant parameters and the optimum combination level of the parameters were obtained. It was found that using a tool rotation of 1000 rpm, plunge depth 11.5 mm and dwell time of 40 s, an improved joint strength can be obtained. The results showed that joint strength was improved by an amount of 20% as compared with the optimum welding parameters to the initial welding parameters. Macrostructure examination plays an important role to determine the joint strength and evaluate the influences of each welding parameters. So, weld morphology was investigated by morphological analysis and visual comparisons. It was also observed failure modes for fractured samples having the highest, moderate and lowest lap joint shear load.

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Improving the joint strength of the friction stir spot welding of carbon steel and copper using the design of experiments method

Multidiscipline Modeling in Materials and Structures ◽

10.1108/mmms-02-2018-0025 ◽

2018 ◽

Vol 14 (5) ◽

pp. 908-922 ◽

Cited By ~ 7

Author(s):

Isam Tareq Abdullah ◽

Sabah Khammass Hussein

Keyword(s):

Carbon Steel ◽

Design Of Experiments ◽

Spot Welding ◽

Shear Force ◽

Pure Copper ◽

Friction Stir Spot Welding ◽

Welding Parameters ◽

Content Type ◽

Rotating Speed ◽

Friction Stir

PurposeThe purpose of this paper is to optimize the welding parameters: rotating speed and plunging depth of carbon steel and pure copper joints using friction stir spot welding (FSSW) with the aid of the design of experiments (DOE) method.Design/methodology/approachCarbon steel and pure copper sheets were welded using the FSSW technique with a cylindrical tool and without a probe. The welding parameters were: rotating speed: 1,120, 1,400 and 1,800 RPM and plunging depth: 0.2 and 0.4 mm. The welding process was carried out both with and without pre-heating. The welded specimens were analyzed using a shear tensile test. A microstructural investigation at the optimum conditions was carried out. The results were analyzed and optimized using the statistical software Minitab and following the DOE method.FindingsPre-heating the sample and increasing the rotating speed and plunging depth increased the tensile shear force of the joint. The plunging depth has the biggest effect on the joint efficiency compared with the rotating speed. The optimum shear force (4,560 N) was found at 1,800 RPM, 0.4 mm plunge depth and with pre-heating. The welding parameters were modified so that the samples were welded at 1,800 RPM and at plunging depths of 0.45–1 mm in 0.05 mm steps. The optimized shear force was 5,400 N. The fractured samples exhibited two types of failure mode: interfacial and nugget pull-out.Originality/valueFor the first time, pure copper and carbon steel sheets were welded using FSSW and a tool without a probe with ideal joint efficiency (95 percent).

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Optimizing the Friction Stir Spot Welding Parameters to Attain Maximum Strength in Dissimilar Joints of Aluminum and Carbon Steel

International Journal of Materials Forming and Machining Processes ◽

10.4018/ijmfmp.2016070104 ◽

2016 ◽

Vol 3 (2) ◽

pp. 64-76

Author(s):

Sundaram Manickam ◽

Visvalingam Balasubramanian

Keyword(s):

Carbon Steel ◽

Rotational Speed ◽

Spot Welding ◽

Dwell Time ◽

Friction Stir Spot Welding ◽

Diameter Ratio ◽

Tool Rotational Speed ◽

Dissimilar Joints ◽

Friction Stir ◽

Tool Diameter

The present investigation is aimed at optimizing the friction stir spot welding (FSSW) process parameters such as tool rotational speed, plunge rate, dwell time and tool diameter ratio, to attain the maximum strength in dissimilar joints of AA6061 aluminum and carbon steel. Experiments were conducted according to the four factor, five level central composite rotatable design matrix. Strength of the joints was evaluated by means of single lap shear test. Optimization was done by response surface method (RSM). A maximum tensile shear fracture load (TSFL) of 9.46 kN was exhibited by a joint welded using following parameters: tool rotational speed of 1000 rpm, plunge rate of 4 mm/ min, dwell time of 5 sec and tool diameter ratio of 3.0.

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Simulation of Friction Stir Spot Welding of Copper and Aluminium During Plunging Phase

Journal of Physics Conference Series ◽

10.1088/1742-6596/2129/1/012002 ◽

2021 ◽

Vol 2129 (1) ◽

pp. 012002

Author(s):

N N S M Shobri ◽

S R Pedapati ◽

M Awang

Keyword(s):

Rotational Speed ◽

Spot Welding ◽

Regression Line ◽

Friction Stir Spot Welding ◽

Peak Temperature ◽

Welding Parameters ◽

Plunge Depth ◽

Friction Stir ◽

Explicit Analysis ◽

Residual Plots

Abstract Simulation is limited and remains briefly addressed in the literature of friction stir spot welding (FSSW) process in joining dissimilar copper and aluminium. Thus, this study simulated the FSSW process of copper and aluminium to investigate the peak temperature during the plunging phase produced by all possible combinations of levels for tool rotational speed, plunge rate, and plunge depth according to the full factorial design. The modeling was established by Coupled Eulerian-Lagrangian (CEL) model and ‘dynamic, temperature-displacement, explicit’ analysis. The highest peak temperature of 994.4 oC was produced by 2400 rpm rotational speed, 100 mm/min plunge rate, and 1.6 mm plunge depth. The combination was suggested to be the optimum welding parameters in joining copper to aluminium as sufficient heat input was essential to soften the area around the welding tool and adequately plasticize the material. Three sets of confirmation tests presented consistent responses with a mean peak temperature of 994.4 °C, which validated that the response produced by the suggested optimum welding parameters was reliable. The statistical result reported that the variability in the factors could explain 84.12% of the variability in the response. However, only the rotational speed and plunge depth were statistically significant. The residual plots showed that the regression line model was valid.

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EFFECT OF ROTATIONAL SPEED AND DWELL TIME ON PHYSICAL AND MECHANICAL PROPERTIES OF FRICTION STIR SPOT WELDING ALUMINIUM 1100 WITH ZN POWDER INTERLAYER ADDITION

Mekanika: Majalah Ilmiah Mekanika ◽

10.20961/mekanika.v18i1.35039 ◽

2019 ◽

Vol 18 (1) ◽

Author(s):

Aditya Noor ◽

Nurul Muhayat ◽

. Triyono

Keyword(s):

Mechanical Properties ◽

Rotational Speed ◽

Spot Welding ◽

Dwell Time ◽

Physical And Mechanical Properties ◽

Friction Stir Spot Welding ◽

Shear Load ◽

Tensile Shear ◽

Lightweight Materials ◽

Friction Stir

<p><em>Friction stir spot welding (FSSW) is one of the development of solid state welding to joint lightweight materials such as aluminium. In the automotive industry, lightweight materials are needed in the structure of vehicle construction to improve efficiency in vehicles. This research aims to find out how the effect of rotational speed and dwell time on physical and mechanical properties on the weld joint of aluminium 1100 with Zn interlayer addition. Variations used in rotational speed 1000, 1250, 1600 rpm and dwell time 6, 7, 8 s. Pullout fracture occur in tensile tests that are getting bigger with increasing rotational speed and dwell time. The results of SEM and EDS observations showed that the metallurgical bonded zone increased and kept the hook defect away. The spread of Zn in the stir zone area causes the formation of solid Al-Zn phase in a solid solution. The hook defect filled with Zn can minimize cracks that occur, so increased the tensile shear load. The highest tensile shear load value of FSSW AA1100 without Zn interlayer is 3.61 kN, while the FSSW AA1100 with Zn interlayer addition is 4.34 kN.</em></p>

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Experimental Study and Numerical Modeling of Friction Stir Spot Welding of Pure Copper Lap Joint

Volume 2B: Advanced Manufacturing ◽

10.1115/imece2014-38033 ◽

2014 ◽

Cited By ~ 1

Author(s):

Ahmed Kamal Mahgoub ◽

Abdelaziz Bazoune ◽

Fadi A. A. Al-Badour ◽

Abdelrahman Shuaib ◽

Gihad Mohamed Karrar

Keyword(s):

Experimental Study ◽

Spot Welding ◽

Dwell Time ◽

Pure Copper ◽

Friction Stir Spot Welding ◽

Fusion Welding ◽

Weld Strength ◽

Tool Rotational Speed ◽

Lap Joint ◽

Friction Stir

Friction stir spot welding (FSSW) is an appropriate process to join materials that are difficult to weld using fusion welding, such as copper. In this paper, an experimental study to weld lap joint of pure copper plates having a dimensions of 100 × 30 × 2 mm is performed, successful spot weld is obtained at tool rotational speed of 1200 rpm, feed rate of 20 mm/min for dwell time of 2 seconds. The tool used in the FSSW has a threaded pin of 5 mm diameter, length of 3.7 mm, and a scrolled shoulder of 11.52 mm diameter. Tensile test and microhardness were performed for the joint and it showed reasonable weld strength. In addition, a numerical model was developed, and the estimated temperatures as well as weld macrostructure matched very well with experimental results.

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Pinless friction stir spot welding of aluminium alloy with copper interlayer

Open Engineering ◽

10.1515/eng-2020-0090 ◽

2020 ◽

Vol 10 (1) ◽

pp. 804-813

Author(s):

Balsam H. Abed ◽

Omar S. Salih ◽

Khalid M. Sowoud

Keyword(s):

Diffusion Process ◽

Spot Welding ◽

Dwell Time ◽

Friction Stir Spot Welding ◽

Welding Parameters ◽

Tensile Shear ◽

Plunge Depth ◽

Friction Stir ◽

Copper Interlayer ◽

Cu Interlayer

AbstractSpot welding joints of Al-Mg-Si alloy (AA6061-T6) were produced with and without the addition of copper interlayer using pinless friction stir spot welding (P-FSSW). To investigate the effects of welding parameters on the metallurgical and mechanical properties of the weldment, various tool plunge depth and dwell time were used. Optical microscopy, scanning electron microscopy, and energy-dispersive X-ray spectroscopy (EDS) have been used for microstructural characterisation.Meanwhile, the mechanical characterisation of the welded joints was evaluated by tensile-shear test. The experimental results showed that a larger bonding area and sound joint were achieved with the addition of Cu interlayer due to the improvement in thermal distribution. Also, an alloying reaction took place between the aluminium substrate and Cu interlayer during P-FSSW, forming intermetallic compounds layer in the interface through the diffusion process. The increasing of dwell time and plunge depth to some extent were beneficial to the formation of the joint and diffusion process, and thus increasing the tensile-shear load of the joints. The observed fracture mode of the joint was either completely shear off in the interface or complete nugget pullout.

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