Enhancing the tribo-mechanical properties of aerospace AL7075-T6 by magnetron-sputtered Ti/TiN, Cr/CrN & TiCr/TiCrN thin film ceramic coatings

Binary (Ti/TiN and Cr/CrN) and ternary (TiCr/TiCrN) thin films were deposited on AL7075-T6 by magnetron sputtering. Microhardness, adhesion strength and pin-on-plate wear tests were performed to investigate coating performance. Field emission scanning electron microscope integrated with focused ion beam milling and energy dispersive X-ray spectroscopy was employed for microstructural and chemical characterizations. The tribo-mechanical test results revealed that Cr/CrN promoted up to 5 times greater hardness, Ti/TiN showed the highest scratch resistance and up to 8 times reduced wear, while TiCr/TiCrN favored the least friction and surface roughness. Furthermore, the excellent tribological properties of coatings correlated with their superior adhesion to AL7075-T6.