ZrN and Zr-SiN coatings were formed using vacuum-arc plasma fluxes deposition system at the substrate bias voltage (U B) ranged from 2 50 to 2 220 V on HS6-5-2 steel substrates. The structural, mechanical and tribological properties were characterized using x-ray diffraction, atomic force microscopy, scanning electron microscopy, optical microscopy, nanoindentation and ball-on-disk test. The surface roughness parameter Ra of ZrN coatings is lower than Zr-SiN coatings. Both roughness Ra of Zr-SiN coatings and the number of surface defects with mainly small dimensions to 1 lm decrease with increasing negative substrate bias voltage. The addition of silicon to ZrN significantly reduces the crystallite size, from about 18.3 nm for ZrN coating to 6.4 nm for Zr-SiN coating both deposited at the same U B = 2 100 V and 7.8 nm for U B = 2 150 V. The hardness of Zr-SiN coatings increases to about 30 GPa with the increase in negative substrate bias voltage (U B = 2 220 V). Adhesion of the coatings tested is high, and critical load is above 80 N and reduces with U B increase. Coefficient of friction determined using AFM shows similar trend as surface roughness in microscale.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.