Abstracts Book - IMRC 2018

• SWS-O020
CHARACTERIZATION OF MULTILAYER PVD COATINGS FOR
TEMPERATURE SENSOR IN THE AIRCRAFT LANDING GEAR
Marvin Montoya Rangel 1 , Joel Diaz Salgado 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 multilayer PVD coatings are used in the aeronautics industry due to high
resistance of pitting corrosion. The results on the electrochemical impedance
spectroscopy of multilayer coatings are presented. The multilayers PVD
AlCrN/TiSi (85/15), AlCrN/Ti + CrSi and AlCrN/AlCr (70/30) + Cr coatings was high
purity targets of AlCr, TiSi in an N atmosphere on Inconel 718. The cross
sectional of coatings have been characterized 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. A electrochemical test
solutions (5 % wt.) NaCl, (2 % wt.) H 2 SO 4 solutions and H 2 0 were used in a three
electrode open cell. The corrosion rate calculated by linear polarization
resistance curves obtained after 55 min in H 2 O (1E-3 mm/year) solution is
smaller than NaCl and H 2 SO 4 (1E-2 mm/year). For AlCrN/AlCr (70/30) + Cr
coatings in H 2 SO 4 had the highest corrosion rate (7.3E-2 mm/year). The
electrochemical behavior of the coatings in the corrosive solutions was
investigated by electrochemical impedance spectroscopy methods (EIS). The EIS
results Nyquist diagrams and Bode plots were modelled using equivalent circuit
in which it exhibited a two time constant system for PVD coating. 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
electrolyte solutions. Finally, EIS measurements were employed to observe the
corrosion progress of multilayer PVD coating on Inconel 718.
Keywords: Multilayer PVD coatings, Electrochemical Impedance Spectroscopy,
Nyquist diagrams
Presenting authors email: joel_diza@hotmail.com