Bhabani Bora (Author) – Mechanical Engineering Department, Indian Institute of Technology (Indian School of Mines), Dhanbad, Jharkhand, India
Somnath Chattopadhyaya (Author) – Mechanical Engineering Department, Indian Institute of Technology (Indian School of Mines), Dhanbad, Jharkhand India
Shubham Sharma (Author) – Department of Mechanical Engineering, IK Gujral Punjab Technical University, Kapurthala, Punjab, India
Huseyin Cagan Kilinc (Author) – Civil Engineering Department, Istanbul Esenyurt University, Istanbul, Turkey

Series: Mechanical Engineering Theory and Applications
BISAC: TEC020000; TEC021030
DOI: https://doi.org/10.52305/QWFC7491

Friction Stir Welding (FSW) is a green solid-state joining process which can easily join alloys that are generally difficult to weld by conventional fusion welding. This process uses a non-consumable spinning tool bit. The relative motion between the tool and the work piece produces heat, which joins the material of two edges by plastic atomic diffusion. This joining technique is energy efficient, environmentally friendly and versatile.

An attempt has been made to review the research papers on experimental work carried out in the field of friction stir welding and its impact on microstructure, fracture surface, and thermal and mechanical properties of welded joints. Also, Tungsten Inert Gas (TIG) and Metal Inert Gas (MIG) welding have been carried out to compare their mechanical and micro-structural properties with FSW. In this experimental work, focus has been placed on:

a) How to conduct the experiments of FSW on AA 6061-T6 (Aluminium Alloy) using ‘Full Factorial’ design of experiment and developing a mathematical model which provides the empirical relationship between the process parameters (Rotational Speed and welding Speed) and the output responses (Maximum Process Temperature (TMax), Maximum Vickers Micro Hardness (HMax), Yield Strength (YS), Ultimate Tensile Strength (UTS) and % Elongation (% E)).
b) The effects of process parameters on temperature distribution and mechanical properties (Tensile properties, Vickers Micro Hardness) of AA 6061-T6 friction stir welded butt joints.
c) How to find the optimum welding parameters that would minimize temperature and maximize mechanical properties.
d) Analyzing thermal properties using simulations in ANSYS software.

Analysis of variance (ANOVA) and scatter diagram have been employed to assess the significant effect of the factors and the adequacy of the models developed for the response variables. The developed mathematical models can be effectively used at 95% confidence level. Also, from the experimental data, it is revealed that FSW joints exhibit superior mechanical properties as compared to the TIG and MIG welded joints.