CFD-Based Analysis and Optimisation of Interfacial Viscosity and Velocity Flow in Dissimilar Friction Stir Lap Welding of Aluminium 6061 and Stainless Steel 304

YADAV, AMIT; JAIN, AJAI; VERMA, RAJIV

doi:10.22075/jhmtr.2026.39160.1843

CFD-Based Analysis and Optimisation of Interfacial Viscosity and Velocity Flow in Dissimilar Friction Stir Lap Welding of Aluminium 6061 and Stainless Steel 304

Articles in Press

Document Type : Full Length Research Article

Authors

AMIT YADAV ¹

AJAI JAIN ¹

RAJIV VERMA ²

¹ NIT Kurukshetra

² NIT Kurukshetra, Kurukshetra, Haryana

10.22075/jhmtr.2026.39160.1843

Abstract

The joining of dissimilar materials such as aluminium and steel is of growing importance in modern manufacturing, owing to the demand for lightweight structures with superior mechanical performance. This study investigates the dissimilar friction stir lap welding of Aluminium Alloy 6061 and Stainless Steel 304, focusing on the influence of four key process parameters: rotational speed, traverse speed, tilt angle, and plunge depth, on weld quality. Specifically, the effects of these parameters on minimum workpiece interface viscosity and maximum weld interface velocity are examined. A mixed-level full factorial design is employed to conduct numerical simulation experiments and develop empirical models for both responses. These models are further analysed using grey relational analysis to identify the optimal parameter combination that simultaneously minimises interface viscosity and maximises interface velocity. The optimal welding condition is achieved at a rotational speed of 1800 RPM, traverse speed of 60 mm/min, tilt angle of 1.5°, and plunge depth of 0.45 mm, corresponding to a minimum interface viscosity of 177000 Pa s and a maximum weld interface velocity of 0.1218 m/s. The combined application of full factorial design and grey relational analysis for multi-response optimisation in dissimilar friction stir lap weld demonstrates the novelty and practical significance of this work.

Keywords

Friction Stir Weld

Computational Fluid-Dynamics

Finite-Volume Approach

Grey Relational Analysis, General Full Factorial Design

Subjects