The influence of multilayer structure on mechanical behavior of TiN/TiAlSiN multilayer coating

Nitride coatings have been generally applied on light alloys like titanium and aluminium to promote their multiple performances, including hardness, thermal stability and wear resistance. In this work, TiAlSiN/TiN multilayered (ML) coating and TiAlSiN single-layer (SL) coating were deposited on TC18 (Ti5Al5Mo5V1CrFe) alloy by Multi-arc ion plating technique. The microstructure and chemical composition of the coatings were evaluated by SEM, XRD and XPS. Additionally, hardness, adhesion and wear resistance were measured through nanoindentation, scratch spectrometer and ball-on-disk tribometer. The results present that both ML and SL coating contain three main phases of TiN, Al2O3 and Si3N4. Nevertheless, the adhesion of ML coating is 62.4 N, compared to that of the SL coating is 51.8 N. The parameter H-3/E-2 as an indication of plastic deformation to evaluate wear resistance shows that the ML coating has high hardness and high toughness concurrently. The tribological study indicated that the wear rate of the ML coated specimen was 1/7 of the SL coated counterpart.

Automated summary

Nitride coatings have been widely used on light alloys like titanium and aluminum to enhance their hardness, thermal stability, and wear resistance. In this study, TiAlSiN/TiN multilayered coating and TiAlSiN single-layer coating were applied on TC18 alloy, with the multilayered coating showing better adhesion, hardness, and wear resistance properties compared to the single-layer coating.