مشخصات پژوهش

صفحه نخست /Correlation between the duty ...
عنوان
Correlation between the duty cycle and the surface characteristics for the nanostructured titanium aluminum nitride coating deposited by pulsed-DC PACVD technique
نوع پژوهش مقاله چاپ‌شده
کلیدواژه‌ها
Nanostructured TiAlN coatings PACVD method Duty cycle Mechanical properties Corrosion behavior
چکیده
The purpose of this paper is to investigate the relation between duty cycle, microstructure and surface properties of the nanostructured titanium-aluminum nitride (TiAlN) coatings produced by using pulsed- DC plasma-assisted chemical vapor deposition (PACVD). In order to evaluate the effects of duty cycle, TiAlN coatings were applied for 150 min in the 30, 40, and 50% of duty cycle at 470 C substrate temperature, 10 kHz frequency, and 3 mbar working pressure. Field emission-scanning electron microscope (FE-SEM), X-ray diffraction (XRD), and Energy-dispersive X-ray spectroscopy (EDS) were used for the coatings characterization. To evaluate the coatings surface properties, Nano-indentation, residual stress tester, Tafel polarization, and electrochemical impedance spectroscopy (EIS) were also utilized. The results implied that microstructure and mechanical properties of the coating have a significant correlation with duty cycle. Due to the fact that nucleation and growth occurs in the off-time, with decrease in duty cycle, the number of nuclei significantly increases. So, when duty cycle declined from 50 to 30%, coating nano-hardness increased from 26 to 31 GPa. Furthermore, corrosion behavior showed that the polarization resistance of the coating deposited at 30% duty cycle, is the highest value in complete accordance with the obtained results from tafel polarization curves (the least corrosion current density).
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