Investigating the Effect of Friction Stir Welding on Microstructure and Corrosion Behaviour of Al-Zn-Mg Alloy

Abstract:

In this work, Friction Stir Welding (FSW) of alloy 7039 was carried out in T4 temper and resulting microstructure and corrosion behaviour of developed weld were studied. FSW transformed the starting microstructure of base metal and formed stirred zone (SZ) and heat affected zone (HAZ) with varying microstructure and precipitate morphology. The observed zones in welded joints exhibited decreased protection to corrosion resistance than base metal. Dissolution of secondary precipitates in SZ and occurrence of precipitate free zones (PFZs) in HAZ enhanced susceptibility to corrosion of HAZ and weld nugget zone (WNZ) than base metal.

• Periodical: Materials Science Forum (Volume 969)
• Pages: 517-523
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.969.517
• Online since: August 2019
• Authors: Chaitanya Sharma, Vikas Upadhyay*
• Keywords: Immersion Corrosion Test, Microstructure, Tafel Polarization, Welding

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