Effect of Modulation Period on the Microstructure and Tribological Properties of AlCrTiVNbN/TiSiN Nano Multilayer Films

The impact of modulation periods on the microstructure, as well as the tribological and mechanical characteristics of the AlCrTiVNbN/TiSiN nano multilayer films, was investigated. The films were prepared with modulation periods ranging from 4 nm to 7 nm, and their properties were explored using X-ray diffraction (XRD), scanning electron microscope (SEM), nanoindentation, and a tribological tester. All nano multilayer films revealed a face-centered cubic (FCC) structure with a preferred planar direction of (200). As the modulation period increased, the XRD peak moved to higher angles, and the interplanar distance decreased. Also, the mechanical properties deteriorated, and the COF rose monotonically as a result. The nano multilayer film with a modulation period equal to 4 nm exhibited a smooth surface with minimal small particles, the highest hardness of 15.51 ± 0.16 GPa and elastic modulus of 182.89 ± 2.38 GPa, the highest values for the ratios of H/E and H3/E2, the lowest average friction coefficient of 0.73, and a wear rate equal to (8.2 9 ± 0.18) × 10−8 mm3·N−1·m−1. The improvement in the properties of the film was ascribed to the coherent growth and alternating stress field between the AlCrTiVNbN and TiSiN layers.