The Effect of Deposition Conditions and Irradiation on the Structure, Substructure, Stress-Strain State, and Mechanical Properties of TiN Coatings

The influence of the displacement potential and the radiation factor on the features of the formation and mechanical properties of titanium nitride coatings obtained by the vacuum-arc method has been established. Important indicators of the process of bombardment by charged ions of the coating surface and the growing surface itself are determined, namely, at the maximum penetration depth of ions reaches (1.5–5 nm) and the number of vacancies (0.45–1.35). The simulation results are compared with actual experiments, and it is established that the above changes do occur. The hardness of TiN coatings was 42–45 GPa. The relaxation process of residual stresses is observed at U_i = −1200 V. As a result, the level of microdeformation is reduced to the value of 0.61%, the size of the crystallites reaches 23 nm. The analysis of the reasons for the observed structural changes is carried out based on the mechanism of formation of surface layers of vacuum-arc coverings in the conditions of the implantation processes stimulated by giving negative potential on a substrate. Irradiation with accelerated argon ions leads to a decrease in the physicomechanical characteristics of the coating (a decrease in the hardness (22–29 GPa) and elastic modulus (~410 GPa)). The changes are more pronounced in coatings TiN applied under high-voltage pulsed conditions.