TY - JOUR
T1 - XPS and EIS studies of sputtered Al-Ce films formed on AA6061 aluminum alloy in 3.5% NaCl solution
AU - Domínguez-Crespo, M. A.
AU - Torres-Huerta, A. M.
AU - Rodil, S. E.
AU - Brachetti-Sibaja, S. B.
AU - De La Cruz, W.
AU - Flores-Vela, A.
N1 - Funding Information:
Acknowledgments 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 Mr. Javier Zapata Torres for his technical support.
PY - 2010/3
Y1 - 2010/3
N2 - X-ray photoelectron spectroscopy (XPS) was used to analyze the composition of films at different deposition parameters of sputtered Al-Ce coatings on AA6061 aluminum alloys. By means of electrochemical impedance spectroscopy (EIS) measurements, the protective character of these coatings was studied for 21 days of exposure in a 3.5 wt% NaCl solution and an attempt was made to establish the relationship between film thickness and chemical composition (Al/Ce, Ce3/Ce4+ ratios) of the surface before and after the electrochemical characterization. XPS studies revealed the presence of the Alo, Al2O3, CeO2 and Ce 2O3 compounds, confirming that the sputtered Al-Ce films were deposited in the metallic form and thereafter were superficially oxidized under ambient conditions. The Al-Ce bonds were overlapped with the signal of cerium oxides. The transport phenomena in the oxide film or controlled diffusion process are strongly dependent on the deposition parameters and exposure time in the aggressive medium. It was also found that in the deposited samples at p4P200t300, the film was still present after 21 days of exposure, although with visible cracks and erosion areas; however, the Ce3/Ce4+ ratio almost remained constant before and after the electrochemical characterization, which explained the barrier properties of these samples as compared with others at different deposition parameters.
AB - X-ray photoelectron spectroscopy (XPS) was used to analyze the composition of films at different deposition parameters of sputtered Al-Ce coatings on AA6061 aluminum alloys. By means of electrochemical impedance spectroscopy (EIS) measurements, the protective character of these coatings was studied for 21 days of exposure in a 3.5 wt% NaCl solution and an attempt was made to establish the relationship between film thickness and chemical composition (Al/Ce, Ce3/Ce4+ ratios) of the surface before and after the electrochemical characterization. XPS studies revealed the presence of the Alo, Al2O3, CeO2 and Ce 2O3 compounds, confirming that the sputtered Al-Ce films were deposited in the metallic form and thereafter were superficially oxidized under ambient conditions. The Al-Ce bonds were overlapped with the signal of cerium oxides. The transport phenomena in the oxide film or controlled diffusion process are strongly dependent on the deposition parameters and exposure time in the aggressive medium. It was also found that in the deposited samples at p4P200t300, the film was still present after 21 days of exposure, although with visible cracks and erosion areas; however, the Ce3/Ce4+ ratio almost remained constant before and after the electrochemical characterization, which explained the barrier properties of these samples as compared with others at different deposition parameters.
KW - AA6061
KW - Al-Ce films
KW - Coatings
KW - Corrosion properties
KW - Magnetron sputtering
UR - http://www.scopus.com/inward/record.url?scp=77949265987&partnerID=8YFLogxK
U2 - 10.1007/s10800-009-0039-4
DO - 10.1007/s10800-009-0039-4
M3 - Artículo
SN - 0021-891X
VL - 40
SP - 639
EP - 651
JO - Journal of Applied Electrochemistry
JF - Journal of Applied Electrochemistry
IS - 3
ER -