ZrN and Zr-Si-N coatings were formed using vacuum-arc plasma fluxes deposition system at the substrate bias voltage (U_B) ranged from − 50 to − 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-Si-N coatings. Both roughness Ra of Zr-Si-N coatings and the number of surface defects with mainly small dimensions to 1 µm 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-Si-N coating both deposited at the same U_B = − 100 V and 7.8 nm for U_B = − 150 V. The hardness of Zr-Si-N coatings increases to about 30 GPa with the increase in negative substrate bias voltage (U_B = − 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.

MoCN coatings have been formed by cathodic arc evaporation using the mixture of acetylene and nitrogen and pure molybdenum target. The surface structure, in conjunction with x-ray data, was analyzed by atomic force microscopy (AFM). The AFM results show differently shaped grain forms on the surface of coatings investigated. The increase in carbon in chemical coatings composition results in the reduction in surface grain size and the increase in roughness of the coatings.