Investigation on the best process criteria for lap joint friction stir welding of AA1100 aluminum alloy via Taguchi technique and ANOVA

Author(s):  
Abolfazl Khalkhali ◽  
Morteza Sarmadi ◽  
Ehsan Sarikhani

Friction stir welding is a novel joining process extensively used for welding of aluminum alloys. It is widely known that the process parameters involved in friction stir welding play a pivotal role in determining the final characteristics and microstructure of the joint. However, it is still unclear that what combination of process parameter values will lead to the optimum joint characteristics. Taguchi technique is a handy and efficient method that has been widely used for performing optimization in manufacturing engineering. In this paper, lap joint friction stir welding was performed on AA1100 and the process parameters were optimized using Taguchi L16 orthogonal design of experiments. Unlike previous studies on optimization of friction stir welding process in aluminum alloys, a more comprehensive approach has been taken towards the number of input and output parameters of the process. Process parameters considered in this study were tool rotational speed, tool traverse speed, tool tilt angle, and tool pin shape. The optimum design was obtained with reference to output parameters including hardness and grain size in the weld center zone, maximum working temperature, joint tensile strength, and elongation as well as the vertical and horizontal forces on the tool during the process. Analysis of variance was additionally performed to evaluate the significance of each design parameter on output parameters. Results gained from analysis of variance indicated that rotational speed and traverse speed were the most critical parameters in determining the weld mechanical properties as well as quality of the weld microstructure. Finally, to validate predicted optimum values based on Taguchi technique, confirmation tests were conducted, where an excellent agreement was observed between the predicted and experimental values, showing accuracy of the employed method and obtained results.

2020 ◽  
Vol 17 (4) ◽  
pp. 491-507 ◽  
Author(s):  
Nitin Panaskar ◽  
Ravi Prakash Terkar

Purpose Recently, several studies have been performed on lap welding of aluminum and copper using friction stir welding (FSW). The formation of intermetallic compounds at the weld interface hampers the weld quality. The use of an intermediate layer of a compatible material during welding reduces the formation of intermetallic compounds. The purpose of this paper is to optimize the FSW process parameters for AA6063-ETP copper weld, using a compatible zinc intermediate filler metal. Design/methodology/approach In the present study, a three-level, three-factor central composite design (CCD) has been used to determine the effect of various process parameters, namely, tool rotational speed, tool traverse speed and thickness of inter-filler zinc foil on ultimate tensile strength of the weld. A total of 60 experimental data were fitted in the CCD. The experiments were performed with tool rotational speeds of 1,000, 1,200 and 1,400 rpm each of them with tool traverse speeds of 5, 10 and 15 mm/min. A zinc inter-filler foil of 0.2 and 0.4 mm was also used. The macrograph of the weld surface under different process parameters and the tensile strength of the weld have been investigated. Findings The feasibility of joining 3 mm thick AA6063-ETP copper using zinc inter-filler is established. The regression analysis showed a good fit of the experimental data to the second-order polynomial model with a coefficient of determination (R2) value of 0.9759 and model F-value of 240.33. A good agreement between the prediction model and experimental findings validates the reliability of the developed model. The tool rotational speed, tool traverse speed and thickness of inter-filler zinc foil significantly affected the tensile strength of the weld. The optimal conditions found for the weld were, rotational speed of 1,212.83 rpm and traverse speed of 9.63 mm/min and zinc foil thickness is 0.157 mm; by using optimized values, ultimate tensile strength of 122.87 MPa was achieved, from the desirability function. Originality/value Aluminium and copper sheets could be joined feasibly using a zinc inter-filler. The maximum tensile strength of joints formed by inter-filler (122.87 MPa) was significantly better as compared to those without using inter-filler (83.78 MPa). The optimum process parameters to achieve maximum tensile strength were found by CCD.


Khalkhali A, Sarmadi M and Sarikhani E. Investigation on the best process criteria for lap joint friction stir welding of AA1100 aluminium alloy via Taguchi technique and ANOVA. Proc IMechE Part E: J Process Mechanical Engineering, first published online August 24, 2016 (DOI: 10.1177/0954408916665651 )


Author(s):  
Shubham Verma ◽  
Joy Prakash Misra ◽  
Meenu Gupta

The present study deals with the application of sequential procedure (i.e. steepest ascent) to obtain the optimum values of process parameters for conducting friction stir welding (FSW) experiments. A vertical milling machine is modified by fabricating fixture and tool ( H13 material) for performing FSW operation to join AA7039 plates. The steepest ascent technique is employed to design the experiments at different rotational speed, welding speed, and tilt angle. The ultimate tensile strength is considered as a performance characteristic for deciding the optimal levels. The mechanical and metallurgical characteristics of the joints are studied by executing tensile and microhardness tests. It is concluded from the graphical analysis of the steepest ascent technique that the optimal maximum and minimum values are 1812–1325 r/min for rotational speed, 43–26 mm/min for welding speed, and 2°–1.3° for tilt angle, respectively. Besides, optical microscope and scanning electron microscope are utilized for microstructural and fractographic analyses for a better understanding of the process.


2021 ◽  
Vol 2021 (6) ◽  
pp. 5340-5345
Author(s):  
WIDIA SETIAWAN ◽  
◽  
BERNADO PASARIBU ◽  
MUHAMMAD BADARUDIN THOHA ◽  
GUSTI KETUT PUDJA ◽  
...  

The lap joint will be used on aluminum 6061 and 10 mm thick brass with the Friction Stir Welding method. The probe used is EMS 45 steel with variations in pin lengths of 11 mm, 11.5 mm and 12 mm. The results of this study are in length 11.5 mm with the highest Vickers hardness value of 104.26 VHn compared to 11 mm and 12 mm pin length is 98.93 VHn and 70.43 VHn. The results of shear stress are 67.32 MPa at 12 mm pin length, higher than the 11 mm and 11.5 mm pin lengths of 40.2 MPa and 42.14 MPa.


2017 ◽  
pp. 1293-1305
Author(s):  
G. Venkateswarlu ◽  
M.J. Davidson ◽  
G.R.N. Tagore ◽  
P. Sammaiah

Friction stir processing (FSP) has been developed on the principles of friction stir welding (FSW) as an effective and efficien new method for grain refinement and microstructural modification, providing intense plastic deformation as well as higher strain rates than other conventional severe plastic deformation methods. FSP produces an equiaxed homogeneous microstructure consisting of fine grains, resulting in the enhancement of the properties of the material at room temperature. The objective of the present paper is to examine the influence of friction stir processing (FSP) parameters namely tool rotational speed (RS), tool traverse speed (TS) and tool tilt angle (TA) on the microstructures of friction stir processed AZ31B-O magnesium alloy. This investigation has focused on the microstructural changes occurred in the dynamically recrystallised nugget zone/ stir zone and the thermo mechanically affected zone during FSP. The results presented in this work indicate that all the three FSP process parameters have a significant effect on the resulting microstructure and also found that the rotational speed has greatly influenced the homogenization of the material. The grain refinement is higher at intermediate rotational speed (1150 rpm), traverse speed (32 mm / min and tilt angle (10). It is established that FSP can be a good grain refinement method for improving the properties of the material.


Author(s):  
Morteza Ghaffarpour ◽  
Mohammad Kazemi ◽  
Mohammad Javad Mohammadi Sefat ◽  
Ahmad Aziz ◽  
Kamran Dehghani

In the present study, friction stir welding (FSW) and tungsten inert gas (TIG) techniques were used to join the dissimilar aluminum alloys of 5083-H12 and 6061-T6. The laboratory tests were designed using design of experiment (DOE) method. Variables for the FSW process were the rotational speed, traverse speed, shoulder diameter, and pin diameter. They changed in ranges of 700–2500 r/min, 25–400 mm/min, 10–14 mm, and 2–4 mm, respectively. In the case of TIG process, the variables were current intensity, traverse speed, and tilt angle. These parameters varied from 80 to 90 A, 200 to 400 mm/min, and 3° to 12°, respectively. The optimum amounts of parameters were obtained using response surface methodology (RSM). The RSM-based model was developed to predict ultimate tensile strength (UTS) of the welds produced. In FSW, the difference between predicted and measured UTS was about 1.28% and in TIG it was 1.78%. The good agreement between experimental and predicted results indicates the high accuracy of the developed model. Mechanical properties and also the microstructure of the welds were compared after optimizing both welding processes using RSM. The results showed that the welds produced by FSW indicated a considerably higher quality and also improved mechanical properties compared to TIG. Properties of the joints obtained by FSW in single-sided joints were more desirable. In the double-sided welds obtained by FSW these differences were of an even higher significance.


Metals ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1480
Author(s):  
Assefa Asmare ◽  
Raheem Al-Sabur ◽  
Eyob Messele

The use of aluminum alloys, nowadays, is swiftly growing from the prerequisite of producing higher strength to weight ratio. Lightweight components are crucial interest in most manufacturing sectors, especially in transportation, aviation, maritime, automotive, and others. Traditional available joining methods have an adverse effect on joining these lightweight engineering materials, increasing needs for new environmentally friendly joining methods. Hence, friction stir welding (FSW) is introduced. Friction stir welding is a relatively new welding process that can produce high-quality weld joints with a lightweight and low joining cost with no waste. This paper endeavors to deals with optimizing process parameters for quality criteria on tensile and hardness strengths. Samples were taken from a 5 mm 6061-T6 aluminum alloy sheet with butt joint configuration. Controlled process parameters tool profile, rotational speed and transverse speed were utilized. The process parameters are optimized making use of the combination of Grey relation analysis method and L9 orthogonal array. Mechanical properties of the weld joints are examined through tensile, hardness, and liquid penetrant tests at room temperature. From this research, rotational speed and traverse speed become significant parameters at a 99% confidence interval, and the joint efficiency reached 91.3%.


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