Abstracts Book - IMRC 2018

• SE4-P002
STUDY OF CORROSION BEHAVIOR OF MULTILAYER PVD
COATINGS BY THE CYCLIC POTENTIODYNAMIC POLARIZATION
CURVES AND ELECTROCHEMICAL IMPEDANCE SPECTROSCOPY
Marvin Montoya Rangel 1 , Citlalli Gaona 1 , Nelson Federico Garza Montes de Oca 1 , Jose Luis
Tristancho Reyes 2 , Patricia del Carmen Zambrano Robledo 1 , Facundo Almeraya 1
1 Universidad Autónoma de Nuevo León, Facultad de Ingeniería Mecánica y Eléctrica, Mexico.
2 Universidad Tecnológica de Pereira, Facultad de Mecánica, Colombia.
The results on the cyclic potentiodynamic polarization curves and
electrochemical impedance spectroscopy of multilayer coatings are presented
in this paper. The multilayers AlCrN/TiSi (85/15), AlCrN/Ti + CrSi and AlCrN/AlCr
(70/30) + Cr coatings was deposited by Physical Vapor Deposition (PVD)
technique high purity targets of AlCr, TiSi in an N atmosphere on Inconel 718.
The structure of the multilayer PVD coatings was investigated by Scanning
Electron Microscopy (SEM) and Energy-dispersive X-ray spectroscopy (EDS). It
has been found an adequate distribution of the coatings on the substrate. The
electrochemical behavior of the coatings in H 2 O, NaCl and H 2 SO 4
electrolytes was investigated by cyclic potentiodynamic polarization and
Electrochemical Impedance Spectroscopy (EIS) methods. For the anodic region
the potentiodynamic polarization curves cyclic showed that substrate and
multilayer PVD coating exhibited a tendency to pseudopasivation behavior in
the different corrosive environments, also it is observed that some curves have
positive hysteresis could be interpreted as susceptibility to pitting corrosion. The
EIS results Nyquist diagrams and Bode plots were fitted using equivalent circuit
in which it exhibited a two time constant system. From this fitting was possible
to follow the penetration of electrolyte into the coating and detect the initiation
of corrosion at the metal/coating interface in H 2 O and NaCl. The effect of
employing different ions in the electrolytes results in different corrosion
behaviour in PVD coating.
Keywords: Multilayer PVD coatings, Cyclic Potentiodynamic Polarization Curves,
Pitting corrosion
Presenting authors email: marmontoya@utp.edu.co