Correlations between the Surface Topography and Mechanical Properties of Friction Stir Welds

Friction stir welding is a modern pressure welding process, which is particularly suitable for aluminum alloys. Several studies have been conducted to investigate the interrelations between the process parameters, such as the welding speed and the tool rotational speed, and the resulting mechanical properties of the joint. This study explored the connections between the surface topography of the welds, such as the flash height and the seam underfill, and their mechanical properties (ultimate tensile strength; elongation at break; and Vickers hardness). For this purpose, a total of 54 welding experiments at three different welding speeds were conducted using the aluminum alloy EN AW-6082-T6. The welded specimens were examined using visual inspection, topographic analysis, metallography, hardness measurements, and uniaxial tensile tests. Afterward, a statistical analysis was performed in order to determine the correlation coefficients between the surface topography and the mechanical properties of the welds. The strongest correlations were between the surface topography and the ultimate tensile strength. Thereby, the most pronounced relations were found between the seam underfill as well as the arc texture formation of the weld and its ultimate tensile strength. The interrelations between the surface topography and the elongation at break, as well as the hardness of the welds, were less pronounced. The higher the welding speed became, the less pronounced the interrelations were. The results show the potential of a non-destructive monitoring system based on the topography to support the prediction of the acceptability of welded parts.

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Prediction and optimization of the mechanical properties of dissimilar friction stir welding of aluminum alloys using design of experiments

Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture ◽

10.1177/0954405416667404 ◽

2016 ◽

Vol 232 (8) ◽

pp. 1384-1394 ◽

Cited By ~ 15

Author(s):

R Palanivel ◽

RF Laubscher ◽

S Vigneshwaran ◽

I Dinaharan

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Friction Stir Welding ◽

Aluminum Alloys ◽

Ultimate Tensile Strength ◽

Design Of Experiments ◽

Process Parameters ◽

Welding Process ◽

Friction Stir ◽

Friction Stir Welding Process

Friction stir welding is a solid-state welding technique for joining metals such as aluminum alloys quickly and reliably. This article presents a design of experiments approach (central composite face–centered factorial design) for predicting and optimizing the process parameters of dissimilar friction stir welded AA6351–AA5083. Three weld parameters that influence weld quality were considered, namely, tool shoulder profile (flat grooved, partial impeller and full impeller), rotational speed and welding speed. Experimental results detailing the variation of the ultimate tensile strength as a function of the friction stir welding process parameters are presented and analyzed. An empirical model that relates the friction stir welding process parameters and the ultimate tensile strength was obtained by utilizing a design of experiments technique. The models developed were validated by an analysis of variance. In general, the full impeller shoulder profile displayed the best mechanical properties when compared to the other profiles. Electron backscatter diffraction maps were used to correlate the metallurgical properties of the dissimilar joints with the joint mechanical properties as obtained experimentally and subsequently modeled. The optimal friction stir welding process parameters, to maximize ultimate tensile strength, are identified and reported.

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Mechanical Properties Of Butt Welded AZ31B Magnesium Alloys

10.32920/ryerson.14648367 ◽

2021 ◽

Author(s):

MD. S.M. Chowdhury

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Fatigue Strength ◽

Ultimate Tensile Strength ◽

Yield Strength ◽

Welding Process ◽

Fusion Welding ◽

Friction Stir ◽

Brittle Phase ◽

Welding Defect

Mechanical properties of friction stir welded (FSWed), double sided arc welded (DSAWed), fiber laser welded (FLWed) and diode laser welded (DLWed) on AZ31B Mg alloy were studied. After welding, grains at the centre became recrystallized. Brittle phase β-Mg₁₇AI₁₂ particles observed at the centre of the joint during fusion welding process. The yield strength (YS), ultimate tensile strength (UTS) and fatigue strength were lower in the FDWed samples than in the DSAWed samples. Welding defect at the bottom of the FDWed joint was observed when right hand thread (RHT) weld tool was considered. In FLWed joint, YS, UTS and fatigue strength, with a joint efficiency of ~91% was achieved while the YS, UTS and fatigue strength of the DLWed joints were notably lower. The DSAWed joints and DLWed joints exhibited a higher strain hardening capacity in comparison with the FSWed joints and FLWed joints, respectively.

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Effect on ultimate tensile strength on varying rotational speed, plunge depth and welding speed during friction stir welding process of aluminium alloy AA7075

Materials Today Proceedings ◽

10.1016/j.matpr.2020.02.444 ◽

2020 ◽

Vol 26 ◽

pp. 2055-2057

Author(s):

Akash Sharma ◽

V.K. Dwivedi ◽

Y.P. Singh

Keyword(s):

Tensile Strength ◽

Friction Stir Welding ◽

Ultimate Tensile Strength ◽

Aluminium Alloy ◽

Welding Speed ◽

Rotational Speed ◽

Welding Process ◽

Plunge Depth ◽

Friction Stir ◽

Friction Stir Welding Process

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Multi-response optimization of friction stir welding process parameters for dissimilar joining of Al6101 to pure copper using standard deviation based TOPSIS method

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1177/0954406219858628 ◽

2019 ◽

Vol 233 (18) ◽

pp. 6473-6482 ◽

Cited By ~ 2

Author(s):

Nidhi Sharma ◽

Zahid A Khan ◽

Arshad Noor Siddiquee ◽

Mohd Atif Wahid

Keyword(s):

Tensile Strength ◽

Friction Stir Welding ◽

Ultimate Tensile Strength ◽

Process Parameters ◽

Welding Speed ◽

Welding Process ◽

Micro Hardness ◽

Friction Stir ◽

Friction Stir Welding Process ◽

Response Optimization

Friction stir welding is a new and effective solid-state welding process for joining dissimilar materials such as aluminum (Al) and copper (Cu). Joint quality of the friction stir welded materials gets influenced by the welding strategy and different friction stir welding process parameters, i.e. rotational speed, welding speed, tool design, tool pin offset, and tilt angle. In this paper, the effect of combination of different friction stir welding process parameters during joining of Al-6101 and pure copper is studied using Taguchi L18 orthogonal array. Four friction stir welding process parameters, i.e. shoulder diameter (A), pin offset (B), welding speed (C), and rotational speed (D) each at three levels except shoulder diameter, which is at two levels are selected. The effect of different combinations of these parameters on ultimate tensile strength and micro-hardness of the joints is investigated. Subsequently, single response optimization for ultimate tensile strength and micro-hardness and multi-response optimization of ultimate tensile strength and micro-hardness taken together is carried out to obtain the optimal combination of the friction stir welding process parameters. Taguchi method is used for single response optimization, whereas Taguchi-based TOPSIS method is employed for multi-response optimization. For single optimization, the optimum combination of the friction stir welding parameters yielding maximum strength and micro-hardness are A1B1C2D2 and A2B1C2D3, respectively. The optimum combination of the process parameters for multi-response optimization is A2B1C2D2. From the results of the study for single- and multi-response optimization, it is revealed that the rotational speed is the most significant process parameter affecting the tensile strength and micro-hardness of the joints followed by the welding speed. Further, the macro/microstructure and micro-hardness profile of the joint obtained at the optimal combination of the multi-response optimization are given and discussed for better understanding of material mixing and joining.

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Mechanical Properties Of Butt Welded AZ31B Magnesium Alloys

10.32920/ryerson.14648367.v1 ◽

2021 ◽

Author(s):

MD. S.M. Chowdhury

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Fatigue Strength ◽

Ultimate Tensile Strength ◽

Yield Strength ◽

Welding Process ◽

Fusion Welding ◽

Friction Stir ◽

Brittle Phase ◽

Welding Defect

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Vibratory weld conditioning during gas tungsten arc welding of al 5052 alloy on the mechanical and micro-structural behavior

World Journal of Engineering ◽

10.1108/wje-06-2020-0211 ◽

2020 ◽

Vol 17 (6) ◽

pp. 831-836

Author(s):

M. Vykunta Rao ◽

Srinivasa Rao P. ◽

B. Surendra Babu

Keyword(s):

Mechanical Properties ◽

Grain Size ◽

Tensile Strength ◽

Ultimate Tensile Strength ◽

Welded Joints ◽

Great Influence ◽

Welding Process ◽

Microstructural Characterization ◽

Content Type ◽

Average Grain Size

Purpose Vibratory weld conditioning parameters have a great influence on the improvement of mechanical properties of weld connections. The purpose of this paper is to understand the influence of vibratory weld conditioning on the mechanical and microstructural characterization of aluminum 5052 alloy weldments. An attempt is made to understand the effect of the vibratory tungsten inert gas (TIG) welding process parameters on the hardness, ultimate tensile strength and microstructure of Al 5052-H32 alloy weldments. Design/methodology/approach Aluminum 5052 H32 specimens are welded at different combinations of vibromotor voltage inputs and time of vibrations. Voltage input is varied from 50 to 230 V at an interval of 10 V. At each voltage input to the vibromotor, there are three levels of time of vibration, i.e. 80, 90 and 100 s. The vibratory TIG-welded specimens are tested for their mechanical and microstructural properties. Findings The results indicate that the mechanical properties of aluminum alloy weld connections improved by increasing voltage input up to 160 V. Also, it has been observed that by increasing vibromotor voltage input beyond 160 V, mechanical properties were reduced significantly. It is also found that vibration time has less influence on the mechanical properties of weld connections. Improvement in hardness and ultimate tensile strength of vibratory welded joints is 16 and 14%, respectively, when compared without vibration, i.e. normal weld conditions. Average grain size is measured as per ASTM E 112–96. Average grain size is in the case of 0, 120, 160 and 230 is 20.709, 17.99, 16.57 and 20.8086 µm, respectively. Originality/value Novel vibratory TIG welded joints are prepared. Mechanical and micro-structural properties are tested.

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Microstructure and Mechanical Properties of Dissimilar Friction Welding Ti-6Al-4V Alloy to Nitinol

Metals ◽

10.3390/met11010109 ◽

2021 ◽

Vol 11 (1) ◽

pp. 109

Author(s):

Ateekh Ur Rehman ◽

Nagumothu Kishore Babu ◽

Mahesh Kumar Talari ◽

Yusuf Siraj Usmani ◽

Hisham Al-Khalefah

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Flow Stress ◽

Intermetallic Compound ◽

Ultimate Tensile Strength ◽

Friction Welding ◽

Welding Process ◽

Weld Interface ◽

Dissimilar Joints ◽

Dissimilar Alloys

In the present study, a friction welding process was adopted to join dissimilar alloys of Ti-Al-4V to Nitinol. The effect of friction welding on the evolution of welded macro and microstructures and their hardnesses and tensile properties were studied and discussed in detail. The macrostructure of Ti-6Al-4V and Nitinol dissimilar joints revealed flash formation on the Ti-6Al-4V side due to a reduction in flow stress at high temperatures during friction welding. The optical microstructures revealed fine grains near the Ti-6Al-4V interface due to dynamic recrystallization and strain hardening effects. In contrast, the area nearer to the nitinol interface did not show any grain refinement. This study reveals that the formation of an intermetallic compound (Ti2Ni) at the weld interface resulted in poor ultimate tensile strength (UTS) and elongation values. All tensile specimens failed at the weld interface due to the formation of intermetallic compounds.

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Effects of Gd, Y Content on the Microstructure and Mechanical Properties of Mg-Gd-Y-Nd-Zr Alloy

Metals ◽

10.3390/met8100790 ◽

2018 ◽

Vol 8 (10) ◽

pp. 790 ◽

Cited By ~ 4

Author(s):

Changping Tang ◽

Kai Wu ◽

Wenhui Liu ◽

Di Feng ◽

Xuezhao Wang ◽

...

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Ultimate Tensile Strength ◽

Solution Treatment ◽

Age Hardening ◽

Uniaxial Tensile ◽

Microstructure And Mechanical Properties ◽

Shaped Particle ◽

Zr Alloy ◽

Non Equilibrium

The effects of Gd, Y content on the microstructure and mechanical properties of Mg-Gd-Y-Nd-Zr alloy were investigated using hardness measurements, X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), and uniaxial tensile testing. The results indicate that the alloys in as-cast condition mainly consist of α-Mg matrix and non-equilibrium eutectic Mg5.05RE (RE = Gd, Y, Nd). After solution treatment, the non-equilibrium eutectics dissolved into the matrix but some block shaped RE-rich particles were left at the grain boundaries and within grains. These particles are especially Y-rich and deteriorate the mechanical properties of the alloys. Both the compositions of the eutectic and the block shaped particle were independent of the total Gd, Y content of the alloys, but the number of the particles increases as the total Gd, Y content increases. The ultimate tensile strength increases as the total Gd, Y content decreases. A Mg-5.56Gd-3.38Y-1.11Nd-0.48Zr alloy with the highest ultimate tensile strength of 280 MPa and an elongation of 1.3% was fabricated. The high strength is attributed to the age hardening behavior and the decrease in block shaped particles.

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Investigations on force generation and joint properties of dissimilar thickness friction stir corner welded AA 5086 alloy

Engineering review ◽

10.30765/er.40.1.09 ◽

2020 ◽

Vol 40 (1) ◽

pp. 67-74

Author(s):

Manigandan Krishnan ◽

Senthilkumar Subramaniam

Keyword(s):

Tensile Strength ◽

Friction Stir Welding ◽

Welding Speed ◽

Welding Process ◽

Spindle Motor ◽

Parent Material ◽

Force Generation ◽

Friction Stir ◽

Current Consumption ◽

Spindle Motor Current

The force generation, joint mechanical and metallurgical properties of friction stir corner welded non-heat treatable AA 5086 aluminum alloy are investigated in this paper. The friction stir welding process is carried out with the plate thicknesses of 6 mm and 4 mm. The welding speed, tool rotational speed and tool plunge depth were considered as the process parameters to conduct the welding experiments. The machine spindle motor current consumption and tool down force generation during friction stir welding were analyzed. The microstructures of various joint regions were observed. The tensile samples revealed the tensile strength of 197 MPa with tool rotational and welding speeds of 1,000 rev/min and 150 mm/min respectively, which is 78 % of parent material tensile strength. A maximum micro hardness of 98 HV was observed at thermomechanically joint affected zone, which was welded with tool rotation of 1,000 rev/min and welding speed of 190 mm/min.

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Mechanical Properties of Herbal Patches from Chitosan-Based Polymer Blends for Medical Applications

Materials Science Forum ◽

10.4028/www.scientific.net/msf.917.52 ◽

2018 ◽

Vol 917 ◽

pp. 52-56

Author(s):

Jirapornchai Suksaeree

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Ultimate Tensile Strength ◽

Polymer Blends ◽

Young’S Modulus ◽

Young's Modulus ◽

Hydroxypropyl Methylcellulose ◽

Peel Strength ◽

Elongation At Break ◽

Zingiber Cassumunar

Recently, Thai herbs are widely used as medicine to treat some illnesses. Zingiber cassumunar Roxb., known by the Thai name “Plai”, is a popular anti-inflammatory, antispasmodic herbal body and muscle treatment. This research aimed to prepare herbal patches that incorporated the 3 g of crude Z. cassumunar oil. The herbal patches made from different polymer blends were 2 g of 3.5%w/v chitosan and 5 g of 20%w/v hydroxypropyl methylcellulose (HPMC), or 2 g of 3.5%w/v chitosan and 5 g of 20%w/v polyvinyl alcohol (PVA) using 2 g of glycerin as a plasticizer. They were prepared by mixing all ingredients in a beaker and produced by solvent casting method in hot air oven at 70±2oC. The completed herbal patches were evaluated for their mechanical properties including Young’s modulus, ultimate tensile strength, elongation at break, T-peel strength, and tack adhesion. The thickness of blank and herbal patches was 0.263-0.282 mm and 0.269-0.275 mm, respectively. Young’s modulus, ultimate tensile strength, elongation at break, T-peel strength, and tack adhesion were 104.73-142.71 MPa, 87.92-93.28 MPa, 154.39-174.98 %, 3.43-4.88 MPa, and 5.29-7.02 MPa, respectively, for blank patches, and 116.83-147.28 MPa, 89.49-100.47 MPa, 133.78-159.27 %, 2.01-3.98 MPa, and 4.03-5.19 MPa, respectively, for herbal patches. We prepared herbal blended patches made from chitosan/PVA or chitosan/HPMC polymer matrix blends incorporating the crude Z. cassumunar oil. They had good mechanical properties that might be developed for herbal medicinal application.

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