Artigo de peri??dico
Localized corrosion resistance of dissimilar aluminum alloys joined by Friction Stir Welding (FSW)
Registro en:
1662-9795
710
10.4028/www.scientific.net/kem.710.41
Autor
BUGARIN, ALINE F.S.
QUEIROZ, FERNANDA M.
TERADA, MAYSA
MELO, HERCILIO G. de
COSTA, ISOLDA
Resumen
2XXX and 7XXX high strength aluminum alloys are the most used materials for
structural parts of aircrafts due to their high strength/weight ratio. Their joining procedure is an
engineering challenge since they present low weldability. Friction Stir Welding (FSW) is a joining
technology developed in the early 90??s. It is a solid-state welding process, without the use of fillers
or gas shield, that eliminates conventional welding defects and has been considered of great interest
for application in the aircraft industry. FSW of aluminum alloys results in four regions of different
microstructures, specifically: the base material (BM), the heat affected zone (HAZ), the thermomechanically
affected zone (TMAZ), and the nugget zone (NZ). The complex microstructure of the
weld region leads to higher susceptibility to localized corrosion as compared to the BM even when
similar alloys are joined. The welding of dissimilar alloys in its turn results in even more complex
microstructures as materials with intrinsically different composition, microstructures and
electrochemical properties are put in close contact. Despite the great interest in FSW, up to now,
only few corrosion studies have been carried out for characterization of the corrosion resistance of
dissimilar Al alloys welded by FSW. The aim of this study is to investigate the corrosion behavior
of aluminum alloy 2024-T3 (AA2024-T3) welded to aluminum alloy 7475-T761 (AA7475-T761)
by FSW. The evaluation was performed in 0.01 mol.L-1 solution by means of open circuit potential
measurements, polarization techniques and surface observation after corrosion tests. Funda????o de Amparo ?? Pesquisa do Estado de S??o Paulo (FAPESP) FAPESP: 13???13235-6