Eliminating intermetallic compounds via Ni interlayer during friction stir welding of dissimilar Mg/Al alloys

Kumar, S and Wu, C (2021) Eliminating intermetallic compounds via Ni interlayer during friction stir welding of dissimilar Mg/Al alloys. In: Journal of Materials Research and Technology, 15 . pp. 4353-4369.

PDF jou_mat_res_tec_15_4353-4369_2021.pdf - Published Version Restricted to Registered users only Download (12MB) | Request a copy

Abstract

There is a substantial demand in transportation industries to join dissimilar Al and Mg alloy to reduce the structural weight further. However, it is challenging to produce high-strength joints of Al/Mg even with friction stir welding due to the formation of intermetallic compounds (IMCs). In a quest to suppress/eliminate the IMCs, we propose to add a Ni interlayer in a sandwich form between the Mg and Al plates. Widely used and industrially applicable AA6061-T6 and AZ31B Mg alloys are taken for experimentation in the present study. The Ni interlayer's effects on microstructure, mechanical properties, and IMCs characterization are studied. The Ni interlayer can drastically cease the molecular diffusion of Mg and Al across their interfaces, and typical IMCs Al3Mg2 and Al12Mg17 are eliminated. Significant dispersion of Ni with Al and Mg is found in the weld zone, which forms Al3Ni and Mg2Ni compounds. The energy-dispersive X-ray spectroscopy confirms the efficacy of Ni addition to wipe out the β and γ IMCs phases. The localized fracture analysis of Ni interlayered joint suggests dual-mode failure, i.e., ductile and brittle. The mechanical testing advocates better weld quality for Ni interlayered joints compared to its conventional ones. © 2021 The Author(s)

Item Type:	Journal Article
Publication:	Journal of Materials Research and Technology
Publisher:	Elsevier Editora Ltda
Additional Information:	The copyright for this article belongs to Elsevier
Keywords:	Aluminum alloys; Binary alloys; Energy dispersive spectroscopy; Friction; Intermetallics; Magnesium alloys; Mechanical testing; Microstructure; Nickel compounds; Research laboratories; Welds, AA6061-T6; Dissimilar al alloys; Friction-stir-welding; High-strength; Intermetallics compounds; Mg alloy; MgAl alloy; Ni interlayers; Structural weight; Transportation industry, Friction stir welding
Department/Centre:	Division of Mechanical Sciences > Mechanical Engineering
Date Deposited:	25 Nov 2021 10:39
Last Modified:	25 Nov 2021 10:39
URI:	http://eprints.iisc.ac.in/id/eprint/70489

Actions (login required)

View Item