Nanostructured surfaces

Effect of substrate bias on structure and mechanical properties of vacuum arc deposited VN coatings
Bortnitskaya M.A.1, Kolodiy I.V.1, Ovcharenko V.D.1, Belous V.A.1, Kuprin A.S.1, Gilewicz A.2, Warcholinski B.2
1 National Science Center “Kharkov Institute of Physics and Technology”, 1 Akademichna st., 61108, Kharkov, Ukraine. 
E-mail: SquirellS06@gmail.com
2 Koszalin University of Technology, Faculty of Technology and Education, Koszalin, Poland.

Hard protective coatings based on transition metal nitrides deposited by PVD technique are widely used in various industrial applications because of their good chemical, mechanical and tribological characteristics [1]. The oxidation of vanadium nitride to vanadium oxides including V2O5 and Magnйli phases from the series VnO2n−1 allows their applications as self-lubricating coatings in tribological contacts working at high temperatures [2]. The properties of the vacuum arc coatings strongly depend on the technological parameters of deposition, such as substrate bias voltage.
The aim of these investigations is to assess the difference in deposition rates, chemical composition, structure and hardness of VN coatings deposited using vacuum arc evaporation with negative substrate bias voltage ranging from -50 to -300 V at nitrogen pressure of 1.5 Pa.
The deposition rate, surface morphology, microstructure, chemical composition and mechanical properties of VN coatings were investigated using scanning electron microscopy, x-ray diffraction analysis, energy dispersive x-ray spectroscopy and nanoindentation.

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