Optimisation of process parameters in submerged friction stir welding of AA7075-T6 for enhanced mechanical properties
Levi P. Cheworei1, Balaji D. Naik2, Srinivasa K. Rao3 and Rambabu G4
Research Scholar, Department of Mechanical Engineering,Andhra University, Visakhapatnam-530003,Andhra Pradesh,India1
Engineering Training Instructor,AI Engineering Services Limited, Trivandrum-695033,Kerala,India2
Head of Department, Metallurgical Engineering,Andhra University, Visakhapatnam-530003,Andhra Pradesh,India3
Professor, Department of Mechanical Engineering,Andhra University, Visakhapatnam-530003,Andhra Pradesh,India4
Engineering Training Instructor,AI Engineering Services Limited, Trivandrum-695033,Kerala,India2
Head of Department, Metallurgical Engineering,Andhra University, Visakhapatnam-530003,Andhra Pradesh,India3
Professor, Department of Mechanical Engineering,Andhra University, Visakhapatnam-530003,Andhra Pradesh,India4
Corresponding Author : Levi P. Cheworei
Recieved : 26-April-2025; Revised : 15-May-2026; Accepted : 18-May-2026
Abstract
Submerged friction stir welding (SFSW) is a variant of friction stir welding (FSW) in which a solid, non-consumable tool is used to weld two similar or dissimilar metals while maintaining low heat input and generating frictional heat along the weld line in a fluid-immersed environment. In the present work, an investigation was conducted to identify the optimal combination of input parameters that maximises the ultimate tensile strength (UTS) and Vickers hardness number (VHN) of an aluminium alloy (AA7075-T6) weld joint. FSW under water-submerged conditions was performed on a vertical lathe to fabricate joints of AA7075-T6 while varying the process parameters to determine the combination that yields the best mechanical properties. The selected process parameters included rotational speed (N, rpm), transverse speed (S, mm/min), and axial force (F, kN). The experimental data were statistically analysed, and response surface methodology (RSM) was employed to develop an optimisation model. Analysis of variance (ANOVA) was used to evaluate the influence of each process parameter on UTS and VHN. The objective of this study was to develop a predictive model for estimating the UTS and VHN of SFSW AA7075-T6 joints under optimal process conditions. The results revealed a maximum UTS of 285.85 MPa and a VHN of 183.76 at process parameters of N = 700 rpm, S = 120 mm/min, and F = 6.41 kN. The developed model demonstrated that the process parameters significantly influence the mechanical properties of the AA7075-T6 joint.
Keywords
Submerged friction stir welding, AA7075-T6 alloy, Response surface methodology, Ultimate tensile strength, Vickers hardness, Process parameter optimisation.
Cite this article
Cheworei LP, Naik BD, Rao SK, G R. Optimisation of process parameters in submerged friction stir welding of AA7075-T6 for enhanced mechanical properties. International Journal of Advanced Technology and Engineering Exploration. 2026;13(138):814-834. DOI : 10.19101/IJATEE.2025.121220396
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