Pitting corrosion of rheocast A356 aluminium alloy in 3.5wt.% NaCl solution
2013; Elsevier BV; Volume: 73; Linguagem: Inglês
10.1016/j.corsci.2013.04.023
ISSN1879-0496
AutoresR. Arrabal, B. Mingo, A. Pardo, M. Mohedano, E. Matykina, Ismael Rodrı́guez,
Tópico(s)Bauxite Residue and Utilization
ResumoIn this study, the microstructure and corrosion behaviour of rheocast and gravity-cast A356 aluminium alloys were examined and compared. Scanning Kelvin probe force microscopy (SKPFM) results proved that large potential differences between iron-containing intermetallics and the α-Al matrix were responsible for the initiation of the attack at the intermetallics/α-Al interfaces. For longer immersion times, corrosion attack proceeded through the eutectic areas. Semisolid processing refined the eutectic silicon and iron-intermetallics and reduced the potential difference between secondary phases and the matrix. This resulted in improved pitting corrosion resistance of the rheocast A356 aluminium alloy.
Referência(s)