Tool Design Effects for FSW of AA7039

Defence Science Journal, 2016

IntroductIon Friction stir welding (FSW) is a relatively new, solid-state welding process, characterised by localised thermo-mechanical phenomena. It has emerged as a candidate process for the successful welding of aluminum alloys that were previously described as not weldable (2xxx series and 7xxx series) 1. The FSW process and its terminology are schematically illustrated in Fig. 1. The important process parameters in FSW are the tool geometry, axial force, rotational speed, traverse speed and, tool tilt angle 1. Many studies have been carried out on the FSW of precipitation hardenable and non heat-treatable aluminium alloys. These studies are mainly focused towards microstructural characterisation 1-4 and effect of welding parameters on mechanical properties 5-7. Role of welding parameters on hardness, fatigue strength, residual stress and microstructural evolution has also been studied by many researchers 1,3,4,8,9. In any process such as FSW, involving complex thermo-mechanical phenomena, the interaction between material and process variables determines the achievable process goals. Inspite of large amount of published work on role of tool pin profile in producing defect-free joints 10-13 , the influence of tool pin profile has not been meticulously correlated with force/torque acting on tool. In analysing the mechanics of friction-stir welding and processing (FSW/P), researchers have employed experimental and numerical techniques to study the flow and consolidation of materials under the shoulder. Many flow visualisation

International Journal of Engineering Research and Technology (IJERT), 2014

https://www.ijert.org/experimental-evaluation-on-the-effect-of-welding-speed-and-tool-pin-profiles-on-friction-stir-welded-joints-on-aa-6082-t6 https://www.ijert.org/research/experimental-evaluation-on-the-effect-of-welding-speed-and-tool-pin-profiles-on-friction-stir-welded-joints-on-aa-6082-t6-IJERTV3IS052131.pdf Friction stir welding (FSW) is a solid state metallic alloys joining process and has emerged as an alternative technology used in high strength alloys that are difficult to join with conventional techniques, in which the raltive motion between the tool and workpiece creates heat which helps the material of two edges being joined by plastic diffusion. In this research rotational speed, welding speed, axial force was taken as process parameters. The aim of the research is to evaluate the effects of different welding speeds (50, 65 & 80 mm/min), rotational speeds (1200& 1500 rpm) and tool pin profiles on the weld quality of AA6082-T-6. Straight cylindrical, taper threaded and hexagonal pin are used as tool pin profiles in this resarch. There is no visual effect found, consequently obtained results explian the stress variation as a functuion of strain. The friction stir welded plates of AA6082-T6 by using the hexagonal pin profile reaches the ultimate tensile strength of 72% of the base metal ultimate strength and there is very negligible eongation. Keywords-FSW, AA6082-T6 aluminium alloy, welding speed, and tool pin profile, mechanical properties.

The flow behavior and strength of joints created using three stirring tools, with right-handed threads at different locations on their cylindrical pins, were investigated. The threading locations on the tools significantly influenced the evolution of the stir zone in the welds and caused material intermixture in various degrees at varying plunging depths. Failure joints were observed in the welds without tool rotation. Force measurements indicated that the highest torque was found in the welds at 900 rpm. Not much difference was observed in the axial force variation between the welds. The peak temperature was obtained at the measured point nearest to the tool shoulder. The maximum joint strength of over 6.5 kN was obtained in the 900 rpm weld with a 9 s dwell time.

International Journal for Research in Applied Science & Engineering Technology (IJRASET), 2022

Friction stir welding (FSW) is a solid-state joining process that uses the frictional heat generated by the rotating tool to soften the metals to form the joint. It is an effective technique for joining dissimilar aluminum alloys and finds its application in various fields such as aerospace and automotive industries. FSW process is energy efficient and environment friendly process. This FSW can produce joints with higher mechanical and metallurgical properties. Formerly, FSW was adopted for low melting metals like aluminum alloys. The various FSW parameters play a vital role in determining the quality of the welded joint. The parameters included in the study of different tool pin profiles (circular, pentagon and taper). FEA analysis will be performed for friction stir welding of Aluminum alloy 5052 and AA6063 at different tool pin profiles using ANSYS. This paper mainly focuses on studying the effect of different tool pin profiles on the microstructure and mechanical properties of the dissimilar AA5052 and AA6063 aluminum alloy joints. The weld quality characteristics like microstructure, micro-hardness, and tensile properties of the joints are analyzed and presented for three different tool pin profiles. It is observed from the result that the joint fabricated using three different tool pin profiles exhibits the better mechanical properties when compared to other joints.

AIP Conference Proceedings, 2018

Dissimilar welding of aluminum is an innovation used to increase the effectiveness and efficiency in making a product or component. It has been applied on the automotive industry, aerospace, and shipbuilding. Aluminum has low weldability in compared with steel material because of the oxide layer on the surface of aluminum. The welding problems of aluminum can be overcome by using a solid state welding such as friction stir welding (FSW). The objective of this study was to determine the strength of the welding joint and the microstructure of dissimilar welding joint with different series of aluminum. The tensile testing was performed with the weld directions of 0° and 45° to assess the formability, hardness testing, and microstructure of FSW. In this study, welding process was conducted to combine aluminum 1100 series (low strength aluminum) and aluminum 6061-T6 series (high strength aluminum) in the 2 mm thickness of aluminum sheet. The analysis was done by making comparison of the strength between dissimilar and similar aluminum series. The results showed that the dissimilar weld types, both in angle orientation of 0° and of 45° had fracture location on the HAZ area of 1100 aluminum series. The highest results of tensile strength were 78.07 MPa and 75.26 MPa for weld angle orientation of 0° and 45°, respectively. Weld angle orientation had significant effect to the strain where value of the welding direction of 0° was 10.99% and of 45° was 13.8%. Hardness test in the weld zone generated diverse values because the material stirring was not homogenous, whereas the similar welding was more stable in the welding area. Microstructure investigation on the dissimilar aluminum welding found a hook defects in the weld nugget. In the HAZ area, the grain size of 6061-T6 increased while of 1100 material decreased. It might be affected by the temperature and the aluminum characteristic. Meanwhile, in weld nugget, the grain size increased due to the stirring tool joint and heating during the welding process.

Transstellar Journals, 2019

The present examination focuses on the evaluation of process parameters on mechanical properties and microstructure study of Friction stir welded (FSW) unlike Aluminum alloys. Their extent of use is in naval and marine applications. Dissimilar FSWed joints were fabricated by varying the rotation speeds, transverse speed and keeping tool geometry as taper with threaded pin profile. The welding parameters & tool probe geometry amusement play larger role in deciding the weld quality. While conducting FSW process, Al 5083 is positioned in advancing side and Al 6061on the retreating side. The experimental results have exposed that the sound defect free the joints obtained by varying the process parameters. From the achieved results, it is to be observed that eminent properties are acquired at a pivot rotational speed of 900rpm, and welding velocity at 40mm/min due to refinement of microstructure. The perceived outcomes were correlated with the microstructure and crack highlights.

Smart Innovation, Systems and Technologies, springer, 2023

The friction stir welding (FSW) process is used in various industries, which includes railways, marine, aerospace, automotive to join copper, aluminum, and magnesium alloys. It is used to combine two similar or dissimilar plates. Different tool pin profiles such as triangular tool, square tool, taper threaded cylindrical tools and cylindrical grooves tool are used at different process parameters and friction stir welding is performed on Aluminium AA6061 plates. Testing of the weldments is done to find tensile, yield strengths, elongation, hardness, and energy absorbed by the weldments. The impact of different tool pin profiles while welding with different process parameters on the mechanical properties of the weldments are evaluated. Destructive and non-destructive tests are conducted on the weldments and based on results it was observed that square tool performed more efficiently followed by cylindrical grooves tool.

2013

In this study two different welding processes have been considered, a conventional tungsten inert gas (TIG) and a relatively new solid state welding known as friction stir welding (FSW). TIG welding process has been performed on Al 6061-T6 of thickness 4mm by using filler metal of Al-Mg alloy type (ER5356) according to AWS classification metal with tungsten electrode (EWth-2) and arc voltage of (12V). Various welding currents of (125, 160, 200, 225) Amp were used under argon as shielding gas of flow rate of (15-20 cf / hour) and welding speed of 280 mm/min. Friction stir welding is carried out using automatic milling machine with five different welding or bed speeds of (25-50-80-100-125 mm/min) and five different tool rotation speeds of (630 -800-1000-1250-1600 rpm). Tool steel of type R18 consists of a shoulder with diameter of (20 mm) and pin of diameter (5.5 mm). Xray radiographic inspection, tensile test and microhardness test of FSW and TIG joints at optimum welding conditions ...

Jurnal Kejuruteraan, 2023

The friction stir welding (FSW) is widely used in the fabrication of Aluminium alloy and other non-ferrous alloy. It has good potential to be used in major industries such as automobiles, aerospace, shipbuilding and can be used in the joining of high strength alloys. The FSW process low distortion and heat affected zone (HAZ) with fine recrystallized microstructure which leads to better mechanical properties at the weld zone and produces great stability. In this study, the different FSW parameters such as weld speed, tool rotation speed, tool tilt angle, feed per min has been discussed. The different types of tool pin profile and shoulder have also been discussed and their impacts on mechanical and microstructural properties at welded joints. Among various welding parameters the rotational speed is the most influencing parameter in FSW. Increasing the rotational speed exhibits the increase at tensile strength and is supposed to improve the mechanical properties. The most affected tool pin profile would be considered to be tapered threaded cylindrical pin profile which makes the adequate mixing of material with better flow ability and provide the fine grains at nugget zone. Comparing the FSW with other arc welding processes, it shows a wide range of environmental benefits which are noticeable such as saving in consumable materials, decrease in consumption of filler material and reduction in grinding wastes. Harmful emissions created from arc welding causes a health hazard to the welder. For achieving the high joint-strength for aerospace aluminium alloys and high temperature sustainable metallic alloys, friction stir welding will be preferred.