TY - JOUR AU - Pardo, A. AU - Feliu Jr, S. AU - Merino, M. C. AU - Mohedano, M. AU - Casajús, P. AU - Arrabal, R. PY - 2010/04/30 Y2 - 2024/03/29 TI - Electrochemical corrosion behaviour of Mg-Al alloys with thermal spray Al/SiCp composite coatings JF - Revista de Metalurgia JA - Rev. metal. VL - 46 IS - 2 SE - Articles DO - 10.3989/revmetalm.0931 UR - https://revistademetalurgia.revistas.csic.es/index.php/revistademetalurgia/article/view/548 SP - 129-142 AB - The corrosion protection of Mg-Al alloys by flame thermal spraying of Al/SiCp composite coatings was evaluated by electrochemical impedance spectroscopy in 3.5 wt.% NaCl solution. The volume fraction of SiC particles (SiCp) varied between 5 and 30%. The as-sprayed Al/SiCp composite coatings revealed a high number of micro-channels, largely in the vicinity of the SiC particles, that facilitated the penetration of the electrolyte and the subsequent galvanic corrosion of the magnesium substrates. The application of a cold-pressing post-treatment reduced the degree of porosity of the coatings and improved the bonding at the coating/substrate and Al/SiC interfaces. This resulted in improved corrosion resistance of the coated specimens. The effectiveness of the coatings slightly decreased with the addition of 5-30 vol.% SiCp compared with the unreinforced thermal spray aluminium coatings. ER -