Structure and Properties of (Ti,Cr)N Films by Arc Ion Plating

Abstract

Ti,Cr)N films were fabricated on the well-polished high-speed-steel substrate under various deposition conditions by arc ion plating. X-ray diffraction was employed to characterize the phase and microstructure of the films, and the preferred orientation of the crystalline plane was discussed in terms of negative bias and nitrogen flow, respectively. The morphology of the films was investigated using scanning electron microscopy. The size and density of macro-particles were compared for different bias and nitrogen flow. The mechanical properties of the films were investigated. The hardness and elastic module were tested by the XP nanoindenter. The results show that the size as well as the number of the macro-particles decreases with increasing negative bias, presenting a smoother surface. The films have preferred (111) plane at low biases but (200) plane at high ones. The hardness and elastic modulus of (Ti,Cr)N films increases with increasing negative bias. Larger hardness can be achieved by increasing nitrogen flow. It is found that the mechanical properties, such as hardness and elastic module of (Ti, Cr)N films are better than those of TiN films, according to the comparison of the experimental results. It indicates that the mechanical properties of TiN can be enhanced by doping Cr. The mechanism is also discussed and analysed by taking deposition parameters into account.