Influence of C2H2 Flows on Microstructure and Corrosion Resistance of TiCN Films Doped with Carbon Atoms

Abstract

Nanosized TiCN/TiN films were deposited on AZ31 by reactive magnetron sputtering under different acetylene flows. The microstructures of obtained films were characterized, and their corrosion behaviors were also investigated. The films doped with carbon atoms under different acetylene flows own different structures and grain sizes. The grain size decreased to some extent, and the film structure changed from polycrystalline to nanocrystalline, with an increase of C2H2 flow. The surface morphology also changed from rough to smooth, with an increase of C2H2 flow. The Tafel curves and electrochemical impedance spectroscopy (EIS) demonstrated that the composite films could greatly improve the corrosion resistance of bare substrates in a 3.5% NaCl solution, and the films’ corrosion resistance is different, owing to their different structures and grain sizes.