Izvorni znanstveni članak
https://doi.org/10.5599/jese.739
Protective films of stearic and octadecylphosphonic acid formed by spray coating
Ekatarina Kristan Mioč
; Laboratory for Corrosion Engineering and Surface Protection – ReCorr, Department of Electrochemistry, Faculty of Chemical Engineering and Technology, University of Zagreb, Marulićev trg 19, 10000 Zagreb, Croatia
Helena Otmačić Ćurković
orcid.org/0000-0002-9794-1274
; Laboratory for Corrosion Engineering and Surface Protection – ReCorr, Department of Electrochemistry, Faculty of Chemical Engineering and Technology, University of Zagreb, Marulićev trg 19, 10000 Zagreb, Croatia
Sažetak
Spray coating formation of stearic and octadecylphosphonic acid films for corrosion protection of cupronickel alloy was studied in this work as a more practical alternative to widely studied dip-coating method. Protective properties of organic films formed under various experimental conditions were examined by electrochemical studies in 3% NaCl solution as a corrosive medium. Polarization resistance measurements as well as electrochemical impedance spectroscopy were employed to follow in time the corrosion behaviour of cupronickel alloy modified by studied organic acids. It was found that among examined experimental parameters, time elapsed between two sprays and number of sprays have the strongest influence on the film stability and its protective properties. This study confirmed that it is possible to form by spray coating the films of stearic and octadecylphosphonic acid
with protective properties that resemble to those of the films prepared by dip-coating method. Differences in corrosion behaviour of samples protected with stearic and octadecylphosphonic acid were attributed to difference in the bond strength between substrate and each organic acid. Studied samples were also examined by the scanning electron
microscopy. Fourier transformed infrared spectroscopy studies showed that crystalline structure dominates in studied films, while contact angle measurements confirmed that modified cupronickel alloy surface exhibits hydrophobic properties.
Ključne riječi
Corrosion; electrochemical impedance spectroscopy; polarization measurements, FTIR, cupronickel alloy
Hrčak ID:
235502
URI
Datum izdavanja:
10.3.2020.
Posjeta: 825 *