Hybrid Self-Reacting Friction Stir Welding of AA 6061-T6 Aluminium Alloy with Cooling Assisted Approach

Kishan Fuse,Vishvesh Badheka

doi:10.3390/met11010016

Abstract

In the present work, self-reacting friction stir welding of 6 mm thick Al 6061-T6 was processed considering two novel approaches as different temperatures of the water (1 °C and 30 °C), and methods of use (spraying and enveloping top surface) using water as cooling media. The four experiments as natural air cooling (NAC), spraying with room temperature water mist (S-RM), spraying with ice water mist (S-IM), and cooling with room temperature water jet (C-RJ) were performed. The thermal profile, microstructure, microhardness, and tensile properties were investigated for all the joints. The lowest hardness location was heat affected zone in NAC and it was the boundary of the thermo-mechanically affected zone and weld nugget zone in all cooling assisted joints. The C-RJ cooling assisted joint resulted in the highest tensile strength of 189.16 MPa which is 8.17% higher than the conventional self-reacting friction stir welded joint.

Highlights

The experiments were performed at four different processing conditions as natural air cooling, spraying with room temperature water mist, spraying with ice water mist, and cooling with room temperature water jet and designated as NAC, S-RM, S-IM, and C-RJ respectively
Following conclusions could be drawn: The following conclusions could be drawn: (1) Coling systems S-RM, S-IM, and C-RJ resulted in a reduction of peak temperature by
(2) The width of the top, middle, and bottom parts of weld nugget zone (WNZ) are reduced in cooling assisted joints compared to the as-welded joint

Summary

Introduction

Self-Reacting Friction Stir Welding of AA 6061-T6 Aluminium Alloy with. Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. The demand for lightweight alloys such as aluminium (Al) alloys is increasing rapidly. Joining of these alloys presents great challenges. The use of conventional fusion welding techniques for joining such alloys is susceptible to generate defects such as oxidation, distortion, porosity, and solidification cracks in joints as the materials are joined by melting and solidification in fusion welding techniques [1,2]. The solidstate joining techniques are a better solution for joining these alloys.

Methods

Discussion

Conclusion