TY - JOUR
T1 - Effective corrosion protection of AA6061 aluminum alloy by sputtered Al-Ce coatings
AU - Domínguez-Crespo, M. A.
AU - Torres-Huerta, A. M.
AU - Rodil, S. E.
AU - Ramírez-Meneses, E.
AU - Suárez-Velázquez, G. G.
AU - Hernández-Pérez, M. A.
N1 - Funding Information:
This study has been financially supported by CONACYT (project number 61354), IPN (projects number SIP-2009-0561, 2009-0499) and SNI. The authors would like to thank Dr. David Turcio-Ortega, Mr. Javier Zapata Torres and H. Zarco for technical support.
PY - 2009/12/30
Y1 - 2009/12/30
N2 - Al-Ce coatings were deposited on silicon and AA6061 aluminum alloy substrates by DC magnetron sputtering using aluminum in combination with pure cerium targets. The materials were characterized by X-ray diffraction (XRD), atomic force microscopy (AFM), scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM) and electrochemical impedance spectroscopy (EIS) in order to consider their application as high corrosion resistance coatings. The corrosion behavior of the films was studied using a NaCl aqueous solution (3.5 wt%). As for the characterization results, an apparent amorphous phase of aluminum oxide with small cerium compounds embedded in the matrix was detected by the X-ray diffraction patterns and HRTEM on the deposited films at 200 W and 4 Pa. At these conditions, AFM and SEM images evidenced crack-free coatings with low-roughness nanometric structures and columnar growth. EIS and Tafel results converged to indicate an inhibition of the corrosion reactions. The film displayed good stability in the aggressive medium and after 1 day of exposure underwent very little degradation. The variations in the impedance and Tafel characteristics were found to occur as a function of cerium content, which provokes important changes in the film protective properties.
AB - Al-Ce coatings were deposited on silicon and AA6061 aluminum alloy substrates by DC magnetron sputtering using aluminum in combination with pure cerium targets. The materials were characterized by X-ray diffraction (XRD), atomic force microscopy (AFM), scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM) and electrochemical impedance spectroscopy (EIS) in order to consider their application as high corrosion resistance coatings. The corrosion behavior of the films was studied using a NaCl aqueous solution (3.5 wt%). As for the characterization results, an apparent amorphous phase of aluminum oxide with small cerium compounds embedded in the matrix was detected by the X-ray diffraction patterns and HRTEM on the deposited films at 200 W and 4 Pa. At these conditions, AFM and SEM images evidenced crack-free coatings with low-roughness nanometric structures and columnar growth. EIS and Tafel results converged to indicate an inhibition of the corrosion reactions. The film displayed good stability in the aggressive medium and after 1 day of exposure underwent very little degradation. The variations in the impedance and Tafel characteristics were found to occur as a function of cerium content, which provokes important changes in the film protective properties.
KW - AA6061
KW - Al-Ce films
KW - Coatings
KW - Corrosion properties
KW - Magnetron sputtering
UR - http://www.scopus.com/inward/record.url?scp=70350763974&partnerID=8YFLogxK
U2 - 10.1016/j.electacta.2009.09.002
DO - 10.1016/j.electacta.2009.09.002
M3 - Artículo
SN - 0013-4686
VL - 55
SP - 498
EP - 503
JO - Electrochimica Acta
JF - Electrochimica Acta
IS - 2
ER -