Effects of nitrogen-argon flow ratio on the microstructural and mechanical properties of TiAlSiN/CrN multilayer coatings prepared using high power impulse magnetron sputtering

This paper introduces a novel TiAlSiN/CrN multilayer film deposited on substrates of silicon Si (100) or tungsten carbide steel using high-power impulse magnetron sputtering. The authors systematically analyzed the effects of N₂/Ar flow ratio on the microstructural and mechanical properties of the thin films using TEM, SEM, XRD, and nanoindentation measurements. SEM images revealed that increasing the N₂/Ar flow ratio led to corresponding decreases in the thickness of TiAlSiN/CrN multilayer films (from 1.9 to 0.5 μm) and the bilayer (from 21.5 to 6.6 nm). XRD and TEM analysis revealed that under the same conditions, the structure of a TiAlSiN monolayer transformed from amorphous to crystallite. Thus, increasing the N₂/Ar flow ratio from 5% to 80% led to a sharp increase in hardness (from 9.8 to 19.6 GPa) and Young's modulus (from 178 to 245 GPa).