Corrosion behaviour of TaN thin PVD films on steels
Por:
Flores J.F., Olaya J.J., Colás R., Rodil S.E., Valdez B.S., Fuente I.G.
Publicada:
1 ene 2006
Resumen:
The corrosion behaviour of tantalum nitride (TaN) thin films deposited on AISI 1018 carbon steel, AISI M2 tool steel and AISI 304 stainless steel has been investigated in an aqueous sodium chloride solution. The films were produced by means of magnetron sputtering plasma deposition. Morphological and microstructuctural characteristics of the films were studied by atomic force microscopy and X-ray diffraction analysis. Potentiodynamic polarisation, electrochemical impedance spectroscopy and cyclic voltammetry techniques were used for electrochemical characterisation. The TaN films displayed lower corrosion current densities than those of the substrates. A relaxation time in the impedance analysis was observed in the 1018/TaN system, two relaxation times were observed in the M2/TaN system, and a diffusion process was found in the 304/TaN system. This indicates that the substrates were not completely isolated from the solution and the defects in the films appear to be detrimental owing to electrolyte penetration through the defects which caused localised corrosion. The corrosion behaviour of the films depends mainly on the electrochemical properties of the substrate. © 2006 Institute of Materials, Minerals and Mining.
Filiaciones:
Facultad de Ingeniería Mecánica y Eléctrica, Universidad Autónoma de Nuevo León, San Nicolás de los Garza, NL, Mexico
Unidad de Materiales, Dpto. de Ingeniería Mecánica y Mecátronica, Ciudad Universitaria, Bogotá, Colombia
Instituto de Investigaciones en Materiales, Universidad Nacional Autónoma de México, México DF, Mexico
Instituto de Ingeniería, Laboratorio de Corrosión Materiales Red Nacional de Corrosión, Universidad Autónoma de Baja California, Mexicali, Baja California, Mexico
Facultad Ciencias Químicas, Universidad Autónoma de Nuevo León, San Nicolás de los Garza, NL, Mexico
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