Effects of Substrate Pulse Bias Duty Cycle on the Microstructure and Mechanical Properties of Ti–Cu–N Films Deposited by Magnetic Field-Enhanced Arc Ion Plating

Ti–Cu–N films were deposited on 316L stainless steel substrates by magnetic field-enhanced arc ion plating. The effect of substrate pulse bias duty cycle on the chemical composition, microstructure, surface morphology, mechanical and tribological properties of the films was systemically investigated. The results showed that, with increasing the duty cycle, Cu content decreases from 3.3 to 0.58 at.%. XRD results showed that only TiN phase is observed for all the deposited films and the preferred orientation transformed from TiN(200) to TiN(111) plane with the increase in duty cycle. The surface roughness and deposition rate showed monotonous decrease with increasing the duty cycle. The residual stress and hardness firstly increase and then decrease afterwards with the increase in duty cycle, while the variation of critical load shows reverse trend. Except for the film with duty cycle of 10%, others perform the better wear resistance.