Influence of Nitrogen on the Microstructure, Hardness, and Tribological Properties of Cr–Ni–B–C–N Films Deposited by DC Magnetron Sputtering

Abstract

Using the direct current reaction magnetron sputtering technique, Cr–Ni–B–C–N films are deposited onto silicon substrates by sputtering Cr–Ni and B–C targets in an Ar/N2 gas mixture. The microstructure, chemical bonds, hardness, and tribological properties of the films are characterized using the X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) methods, and microindentation and tribological tests. The experimental results show that the microstructure and properties of the films change upon incorporation of nitrogen into the film composition. The Cr–Ni–B–C–N films are mainly composed of the nanocrystalline CrN phase with some fractions of the Ni, Cr2O3, and B2O3 crystalline phases embedded in a mixed amorphous environment. Addition of nitrogen gives rise to an increase in the film hardness to a maximum value of about 17 GPa at FN2 = 40 cm3/min, and then the hardness sharply decrease with a further increase in the FN2 flow rate. The incorporation of nitrogen into the structure of films improves their tribological and adhesion properties.