Crystal structure and tribological properties of ZrAlMoN composite films deposited by magnetron sputtering

Quaternary zirconium aluminum molybdenum nitride (ZrAlMoN) composite films with different molybdenum content were deposited using reactive magnetron sputtering. The results showed that the films at 6.7 at.% molybdenum. The room temperature wear rate first maintained its value of ∼3.5 × 10−7 mm−3 N−1 mm−1 at 0–8.6 at.% molybdenum and then dropped to ∼5.0 × 10−8 mm−3 N−1 mm−1 at 12.6 at.% molybdenum, while further increasing in molybdenum content results in the increase of wear rate. The roughness of the film and the appearance of fcc-Mo2N phase were considered as the main factors of the wear rate. For the tribological properties of the film at 13.8 at.% molybdenum, the increase in temperature could induce the main wear mechanism changing to oxidation wear. The change in the wear mechanism resulted in the decreasing in the wear rate as well as also led to the friction coefficient increased at first from RT to 500 °C and then started decreasing at further elevated temperature. •The incorporation of molybdenum into ZrAlN matrix decreased the room temperature friction coefficient.•ZrAlMoN films at 34.0–40.5 at.% molybdenum exhibited excellent the room temperature wear resistance.•ZrAlMoN film at 13.8 at.% molybdenum exhibited a friction coefficient of ∼0.5 at 700 °C against a alumina counterpart.