Effect of Welding Parameters on the Corrosion Behavior of Dissimilar Alloy Welds of T6 AA6061 Al-Galvanized Mild Steel

Partial replacement of steel by Aluminium (Al) alloys is a promising approach adopted by automotive sector to improve fuel efficiency without compromising on the strength. However, this results in the generation of dissimilar welds of Al alloys and steel. Understanding the corrosion behavior of Al a...

Full description

Saved in:
Bibliographic Details
Published inJournal of materials engineering and performance Vol. 27; no. 10; pp. 5518 - 5531
Main Authors Sravanthi, S. S., Acharyya, Swati Ghosh, Phani Prabhakar, K. V., Padmanabham, G.
Format Journal Article
LanguageEnglish
Published New York Springer US 01.10.2018
Subjects
ALUMINIUM ALLOYS
BRAZING
Characterization and Evaluation of Materials
Chemistry and Materials Science
Corrosion and Coatings
Engineering Design
FIELD EMISSION
GAS WELDING
HARDNESS
HEAT TREATMENTS
INTERGRANULAR CORROSION
INTERMETALLIC COMPOUNDS
LAYERS
MATERIALS SCIENCE
PRECIPITATION
Quality Control
Reliability
Safety and Risk
SCANNING ELECTRON MICROSCOPY
STEELS
THICKNESS
Tribology
WELDED JOINTS
X-RAY DIFFRACTION
joining
brazing
weld corrosion
x-ray
Online AccessGet full text

Cover

More Information
Summary:Partial replacement of steel by Aluminium (Al) alloys is a promising approach adopted by automotive sector to improve fuel efficiency without compromising on the strength. However, this results in the generation of dissimilar welds of Al alloys and steel. Understanding the corrosion behavior of Al alloys–steel welds as a function of welding parameters is critical in the successful application of such alloys. The present study reports the intergranular corrosion behavior of T6 heat-treated AA6061 Al alloy-galvanized mild steel lap joints, welded by metal inert gas welding–brazing technique as a function of different welding parameters, viz. weld speed (4-6 m/min) and wire feed rate (0.8-0.9 m/min), following ASTM G 67-04. Weld characterization was performed by field emission scanning electron microscopy (FESEM), x-ray diffraction and nano-hardness measurement. Results indicate heavy dissolution and metal loss at the interface. A high volume fraction of Al-Fe intermetallics was precipitated at the weld interfaces, resulting in high hardness and higher localized corrosion. The thickness of Al-Fe intermetallic layer increased with increasing wire feed rate and lower weld speed which enhanced the severity of galvanic and intergranular corrosion.
ISSN:1059-9495
1544-1024
DOI:10.1007/s11665-018-3596-z