Magnetron sputtered Cr-Ni-N and Ti-Mo-N films: Comparison of mechanical properties

This article reports on structure and mechanical properties of Cr-Ni-N and Ti-Mo-N films with a low (< 10 at.%) content of Ni or Mo, respectively. The films were deposited by reactive sputtering using d.c. unbalanced magnetron equipped with a round planar Cr target fixed to the magnetron cathode with a Ni ring or alloyed TiMo (90:10 at.%) target. The investigation of sputtered films showed that: (i) both Cr-Ni-N and Ti-Mo-N films can form a superhard material with a maximum microhardness H_max of approximately 45 GPa; (ii) the films with H_max exhibit a single-oriented structure and; (iii) the Cr-Ni-N films exhibit a higher resistance to plastic deformation compared to the Ti-Mo-N films. The relationships between microhardness, H, reduced Young's modulus, E^* = E/(1 - ν²), and elastic recovery, W_e, evaluated from loading/unloading curves measured using a computer-controlled microhardness tester Fisherscope H 100, are given; here E and ν are the Young's modulus and Poisson ratio, respectively. The production of a high-temperature (β-Ti,Mo)(110) phase in pure Ti-Mo alloy film sputtered on unheated steel substrate is also reported.