JOURNAL OF THE FACULTY OF ENGINEERING AND ARCHITECTURE OF GAZI UNIVERSITY, no.2, pp.795-806, 2023 (SCI-Expanded)
Aluminum alloys are alloys that are widely used in many sectors due to their high specific strength and are constantly being developed to adapt to today's developing technology. Among these alloy groups, the use of 2XXX and 7XXX series alloys, which are alloy groups that can be hardened by precipitation hardening, is even more common. In this study, an amorphous tantalum-oxide layer was coated by magnetron sputtering method in order to improve the wear resistance of 7075 aluminum alloys. It was applied to the sample groups after polished, sandblasted, alkali, and alkali acid treatments, and the effect of the surface treatments applied before coating on the wear performances after coating was investigated. The effect on the surface morphologies after coating was investigated using scanning electron microscopy (SEM) and energy dispersion spectroscopy (EDS), and their structural analysis was investigated by the X-ray diffraction (XRD) method. The wear behavior of the samples was determined by the ball-on disc wear test performed at room temperature under dry sliding conditions and by SEM examinations, wear track profile measurements, average volume loss calculations and friction coefficient evaluations performed after wear. After the coating process, Ta2O5 coating was obtained in an amorphous structure without cracks, voids, and heterogeneity. Coating thicknesses were measured as approximately equal to 2.5-5 mu m. The highest wear resistance among all samples was observed in the samples coated after alkali and alkali acid treatments, and it was observed that the volume losses after wear decreased by 69-77% compared to the polished and untreated sample.