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In this study, TiN coatings were deposited on Ti-6Al-4V alloy surface using cathodic arc evaporation (CAE) deposition process at three different bias voltages (-150, -200 and -250 V) applied to the substrate. In this regard, the effect of bias voltage on the microstructure and corrosion behaviour of coatings was studied. The microstructure of the coated specimens was analysed by scanning electron microscopy (SEM), X-ray diffraction (XRD) and atomic force microscopy (AFM). The corrosion behaviour of the coatings was studied by potentiodynamic polarization (PDP) experiments and electrochemical impedance spectroscopy (EIS) in the simulated media. Studies on SEM images showed that formed coatings at bias of -200 V exhibited the least amount of needle like cavities (0.4%) and macroparticles. Studying the effect of bias voltage on the corrosion behaviour of the coatings deposited at three bias voltages showed that the maximum corrosion resistance was obtained at -200 V and this voltage had the least current density in polarization measurements (5.59× 10-7 A/cm2). So, it was considered as the optimal bias voltage. [ABSTRACT FROM AUTHOR]

In this investigation, Ti/TiN nanolayer and TiN single layer coatings were coated on substrate of AISI 316L stainless steel by applying physical vapor deposition (PVD) using the type of cathodic arc evaporation (CAE). The evaluation of microstructure were carried out using x-ray diffraction (XRD), nanoindentation, atomic force microscopy (AFM) as well as scanning electron microscopy (SEM). Polarization and impedance tests were utilized to study the coatings corrosion behavior in the simulated body solution (SBF) in different immersion times. Utilizing CAE technique, high density and adhesion Ti/TiN nanolayer and TiN single layer coatings were successfully made. The corrosion results showed that Ti/TiN nanolayer coating had an exceptionally high polarization resistance compared to 316L substrate and TiN single layer coating. Furthermore, the corrosion results indicated the desired corrosion behavior in the nanolayer coating towards the single layer within the SBF, as a result of the distinct layers presence resulting in a barrier against penetration of the corrosive media. [ABSTRACT FROM AUTHOR]

In this paper, corrosion behavior of single and multilayer (TiN, CrN and TiN/CrN) deposited coatings on Ni-Cr dental alloy in artificial saliva using cathodic arc evaporationphysical vapor deposition (CAE-PVD) technique were investigated. The corrosion behavior of uncoated and coated Ni-Cr prosthetic dental alloy has been investigated electrochemically in addition to the other way represented by the quantity measurement of corrosion products which is resulted from the Ni-Cr dental alloys. Fusayama artificial saliva has been utilized as media for measuring all electrochemical behaviors. The surfaces of samples have been analyzed using X-ray diffraction (XRD), energy dispersion spectroscopy (EDS), and scanning electron microscopy (SEM). The results indicated that the coating procedure that has applied to Ni-Cr dental alloy may change wettability by decreasing the hydrophilicity of the surface. The results indicated that the strongest hydrophobic character is exhibited by CrN coating. Potentiodynamic polarization and Nyquist plots showed that CrN coating had an exceptionally high polarization resistance compared to Ni-Cr dental alloy, TiN and TiN/CrN coatings. [ABSTRACT FROM AUTHOR]