13 Infuence of Welding parameters on Mechanical property during Friction Stir Welded joint on Aluminium Alloys: A Review Aditya Mamgain, Vivek Singh & Ajay Pratap Singh Department of Mechanical Engineering, AKGEC, Ghaziabad, Uttar Pradesh. *Corresponding author: vivekgwt@gmail.com Received 12 February 2022, Received in revised form 24 June 2022 Accepted 28 July 2022, Available online 30 January 2023 ABSTRACT 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 fne 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 profle 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 infuencing 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 profle would be considered to be tapered threaded cylindrical pin profle which makes the adequate mixing of material with better fow ability and provide the fne grains at nugget zone. Comparing the FSW with other arc welding processes, it shows a wide range of environmental benefts which are noticeable such as saving in consumable materials, decrease in consumption of fller 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. Keywords: Aluminium; tool design; rotational speed; welding tool speed; tool profle; mechanical properties Jurnal Kejuruteraan 35(1) 2023: 13-28 https://doi.org/10.17576/jkukm-2023-35(1)-02 INTRODUCTION Friction stir welding (FSW) is a solid-state welding process which has been recognized for its potential of joining for high strength aluminium alloys. It was frst invented and patented by TWI in the year 1991. During the development phase, the friction welding only restricted to aluminium alloy and mainly used to reduce the weight of aircraft but with the span of time, its research area increased to a range of materials, which is possible due to development in tool profles. The aluminium alloys have rapidly gathered attention for a wide range of structural application as well as for innovation in improvement of the welding technique. It is being extensively used for similar as well as dissimilar joining of Al, Mg, Cu, Ti and their alloys. Possibly it is diffcult to join dissimilar material using solid-state joining methods without having the compatibility issues of physical properties of the materials as well as formation of intermetallic compounds. Hence, a suitable interlayer which prevents the formation of intermetallic compounds is often employed in such cases. Friction stir welding (FSW) has emerged as one of the vital alternative technologies which has good potential to use in major industries like automobiles, aerospace, shipbuilding, railways and can be used in high strength alloys. With the use of friction stir welding, the common problems of fusion welding such as solidifcation, liquation cracking and porosity have become vanished. As the composite materials have hardness, rigidity, fatigue strength, fexural strength, modulus of rigidity, etc. FSW is very suitable for the composite material. The heat is generated through the translation rotating of a non-consumable tool which increases the temperature of material and leads to a fne grain structure being produced in the weld area which raises the mechanical strength of the material. During FSW process at the faying surface the advancing side from where material starts melting and the other is the retreating side where material gets cooled. Material fow path also possess the responsibility for better mixing of material. However, attentive choices of welding parameters were required for enhancing the microstructural and mechanical properties. During the joining of soft materials like aluminium alloys, FSW becomes the frst priority compared with any other fusion welding process as it has other environmental benefts. The illustration of FSW process is depicted in Figure 1. It was initially developed for only aluminium alloys but with the glimpse of time it becomes suitable for