Microstructure and Corrosion Properties of the Plasma-MIG Welded AA5754 Automotive Alloy

A. Abouarkoub^1*, G. E. Thompson², X. Zhou², G. Scamans³

¹The Libyan Petroleum Institute, Tripoli, Libya.
²School of Materials, The University of Manchester, Manchester, UK.
³Innoval Technology Limited, Banbury, UK.

DOI: 10.4236/jmmce.2015.34034                

Abstract

The influence of heating cycles during plasma metal inert gas (MIG) welding on the microstructure and corrosion properties of the AA5754 automotive alloy has been investigated. The high heat input during plasma-MIG welding results in a significant modification in the microstructure of the AA5754 alloy adjacent to the fusion boundaries. As a consequence of partial melting of the Al-Fe-Mn-(Si) intermetallics at the partially melted zone (PMZ) and segregation of the high melting point elements (particularly Fe and Mn) toward the fusion zone, severe galvanic corrosion attacks can be enhanced along the PMZ of the AA5754 weld during exposure to aqueous corrosion environments.

Keywords

Plasma-MIG Welding, AA5754, Microstructure, Corrosion, Partially Melted Zone

Conflicts of Interest

The authors declare no conflicts of interest.

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