Adrián Claver1, Iker Alfonso1, Tamara Orozb, Beatriz Yécorab, Diego Rodrigob, Iñaki Zalakain1, José Antonio García Lorente1
1Universidad Pública de Navarra (UPNA), Pamplona, Spain 2Lurederra, Los Arcos, Navarra, Spain
Magnesium alloys have emerged as promising materials for use in automotive, biomedical, and aerospace industries thanks to their low density, favorable mechanical properties, and good biocompatibility. Nonetheless, their limited corrosion resistance has hindered broader industrial utilization. Coatings produced by Physical Vapor Deposition (PVD) have proven to be effective in enhancing the corrosion resistance and tribological performance of different alloys. However, issues such as insufficient substrate–coating adhesion and the propagation of corrosion through the columnar structure of the coatings, along with the lack of related research, highlight the need for continue working to improve these systems.
In this study, multilayer PVD coatings based on TiN (AlTiN, AlTiCrN, TiSiN, TiN) have been deposited on Mg alloys, and their corrosion and tribological properties have been studied. Coatings architecture has been optimized, starting from monolayers and continuing with the combination of different layers and the adjustment of deposition processes. Furthermore, the PVD coatings that presented the best results have been combined with a nanotechnology-based ceramic coating (nano-ceramic coating) top layer. Scanning Electron Microscope (SEM), Energy Dispersive X-ray spectroscopy (EDX), Glow Discharge Optical Emission Spectroscopy (GDOES) and X-ray diffraction (XRD) have been used to carry on the structural and composition characterization. Tribomechanical characterization has been done using nanoindentation, scratch test and Pin-On-Disk tribological tests. Corrosion resistance has been evaluated by potentiodynamic and immersion tests. The results have shown that multilayer structures combined with nano-ceramic coatings can be an effective way to improve both, corrosion and wear resistance of Mg alloys.