Properties of Titanium Carbonitride TiCN Coatings Obtained by Vacuum Arc Deposition

Abstract

A comprehensive study is performed on the effect of vacuum arc conditions on the formation of TiCN coatings, specifically focusing on parameters such as the bias potential applied to the substrate, nitrogen partial pressure, and the composition of the C₂H₂–N₂ gas mixture. Our investigation encompassed analyses of the coatings’ chemical composition, structure (lattice parameter, texture factor, orientation, grain size, level of microstrains), and mechanical properties (microhardness, adhesion strength indicators, and coefficient of friction). The results reveal that the coatings predominantly exhibit a polycrystalline nature and possess a cubic B1-NaCl structure, characterized by visible diffraction peaks in the range of 2θ from 30° to 80°, corresponding to reflections (111), (200), (220), and (222). The lattice parameter of TiN was found to increase from 0.4291 to 0.4301 nm with variations in the concentration of C₂H₂, while the texture coefficient concurrently increased from 5.91 to 5.97. The hardness of the coatings at a bias potential U_bias = –200 V exhibited variation from 31.7 to 33.9 GPa, depending on the C/N ratio. Variations in the elemental composition of the coatings led to changes in adhesion strength, with failure occurring at a load F = 62.1 N. The coefficient of friction was measured at μ = 0.45 under these conditions.