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Super hard coatings have been applied to increase the lifetime and to improve the efficiency of machining tools for drilling, cutting, and molding. [1] For this, physical vapor deposition (PVD) method is mostly applied. They have been reported to increase the abrasive wear resistance and to increase the economical benefits of coated materials. [2-4]. In the present study, a nanostructured Cr-Al-N thin film with different Al content (0 to 50 at.%) have been deposited using radio-frequency (R.F) reactive magnetron sputtering system on Si (100) wafer and XC100 steel substrate without heating. The structural evolution and morphological changes as a function of the Zr content were performed using XRD, (EDS, WDS), WPS, XPS, SEM, AFM, Nanoindentation, Scratch adhesion. The tribological performances were evaluated using a ball-on-disk type Oscillating tribometer. The tests were carried out under normal loads of 2, 4 and 6 N respectively, with an alumina ball (Al₂O₃) as a counter face. Different concentrations of Aluminium (Al) (0 – 50 at.%) were studied. The results show, that, with increasing Al content, the film structure changed with the coexistence of (Cr-N, Al-N) crystallographic orientation mixture. The films formed a (Cr, Al) N solid solution where Al atoms substitute Cr atoms, The crystallite size of the CrAlN system was reduced to 10.8 nm at 31.8 at.% Aluminium content. CrN Lattice parameter increased from 4.17 to 4.32 í… with the crystallite size refinement. Morphological studies of the ï¬lms showed that the roughness continuously decreased with increasing zirconium content, exhibiting a value of 11.2 nm at 31.8 at.% Aluminium. The mechanical parameters (H, σ, E, H/E and H3/E2) were significantly improved in comparison to binary films, especially at 30 at. % Al. The friction and wear rate tends to decrease with increasing zirconium content, reaching the lowest value of 1.95 í— 10−2 µm3/(N.µm) at 31.8 at.% zirconium. The sliding wear rate and coefficient of friction were lower in the samples with 31.8 at.% zirconium content. The improved friction and wear resistance were attributed to the grain reï¬nement strengthening mechanism at 31.8 at.% of zirconium.