Abstract
Background: The primary objective of this study is to assess the impact of welding
conditions on the mechanical properties of friction stir-welded butt joints created from two distinct
aluminium alloys, namely, AA6061 and AA7075. Friction stir welding (FSW), known for its innovation
and low-energy solid-state bonding technique, was employed in this research.
Methods: FSW experiments were carried out on both AA6061 and AA7075 alloys using a computer
numerical control (CNC) machine. The selection and design of the tool geometry were meticulous,
with an emphasis on new pin profiles that are nearly flat at the weld contact point. Precisely,
four distinct tool geometries were machined from HC-HCr (High carbon, high chromium steel):
Circular, Square, Tapered third, and Triangular. Critical process variables that significantly influence
weld quality include rotation speed (800 rpm-1400 rpm) and traverse speed (12 to 25
mm/min). These variables were carefully optimized to achieve flawless welds. During the friction
stir welding process, the nugget zone undergoes significant deformation, leading to the formation
of a new microstructure that substantially impacts the mechanical properties of the joint.
Results: This study comprehensively investigates the thermal and mechanical properties of friction
stir welding using aluminium alloys AA6061 and AA7075, considering various tool shapes.
Among the four tool shapes employed, two were found to yield higher hardness values (referred to
as BH). Notably, the square-shaped tool produced the highest temperature, reaching up to 690ºC,
as determined by thermocouple readings. Based on the findings, the optimal FSW parameters for
enhancing hardness involve an axial feed and spindle speed of 800 rpm combined with a feed rate
of 15 mm/min. These parameters were identified as crucial for achieving the desired mechanical
properties in the friction stir-welded joints.
Conclusion: This study presents new developments in FSW technology, which may have patent
implications.
Keywords:
Thermal analysis, friction stir welding (FSW), brinell hardness, AA6061, AA7075, wear analysis.
[29]
Ravikumar S, Rao VS, Pranesh RV. Effect of process parameters on mechanical properties of friction stir welded dissimilar materials between AA6061-T651 and AA7075-T651 alloys. Int J Adv Mech Eng 2014; 4(1): 101-14.
[41]
Yunus MOHAMMED, Alsoufi MS. A statistical analysis of joint strength of dissimilar aluminium alloys formed by friction stir welding using taguchi design approach, anova for the optimization of process parameters. IMPACT: Int Res J Eng Technol 2015; 3(7): 63-70.
[43]
Boşneag A, Constantin MA, Niţu E, Iordache M. Friction Stir Welding of three dissimilar aluminium alloy used in aeronautics industry. IOP Conf Ser Mater Sci Eng 2017; 252(1): 012041.
[49]
Anbunathan PE, Perumal G, Senthilkumar N. Characterization and wear studies on non-asbestos organic fiber reinforced low metallic friction composites. IJMPERD 2019; 9: 133-43.
[50]
Bosneag A, Constantin MA, Nitu E, Iordache M. Friction stir welding of three dissimilar aluminium alloy: AA2024, AA6061 and AA7075. IOP Conf Ser: Mater Sci Eng 2018; 400(2): 022013.
[60]
Mesbah A, Belabed Z, Amara K, Tounsi A, Bousahla AA, Bourada F. Formulation and evaluation a finite element model for free vibration and buckling behaviours of functionally graded porous (FGP) beams. Struct Eng Mech 2023; 86(3): 291.
[61]
Xia L, Wang R, Chen G, Asemi K, Tounsi A. The finite element method for dynamics of FG porous truncated conical panels reinforced with graphene platelets based on the 3-D elasticity. Adv Nano Res 2023; 14(4): 375-89.
[62]
Katiyar V, Gupta A, Tounsi A. Microstructural/geometric imperfection sensitivity on the vibration response of geometrically discontinuous bi-directional functionally graded plates (2D FGPs) with partial supports by using FEM. Steel Compos Struct 2022; 45(5): 621-40.
[64]
Cuong-Le T, Nguyen KD, Le-Minh H, Phan-Vu P, Nguyen-Trong P, Tounsi A. Nonlinear bending analysis of porous sigmoid FGM nanoplate via IGA and nonlocal strain gradient theory. Adv Nano Res 2022; 12(5): 441.
[65]
Kumar Y, Gupta A, Tounsi A. Size-dependent vibration response of porous graded nanostructure with FEM and nonlocal continuum model. Adv Nano Res 2021; 11(1): 01-17.