Microstructure, oxidation resistance, mechanical and tribological properties of Mo–Al–N films by reactive magnetron sputtering

• Mo–Al–N films were deposited by reactive magnetron sputtering.
• The oxidation resistance temperature of Mo–Al–N films were higher than Mo2N.
• The films with a Al content in the range of 4.05 at.%–9.49 at.% were found to be optimized for wear resistance applications.

Mo–Al–N films with various Al content (3.7 at.%–18.3 at.%) were deposited by reactive magnetron sputtering and the effects of Al content on the microstructure, mechanical, oxidation resistance and tribological properties of Mo–Al–N films were investigated. The results showed that the synthesized Mo–Al–N films exhibited the face-centered cubic (fcc) structure with (111)-preferred orientation. The oxidation resistance of Mo–Al–N films increased with increasing Al content. The hardness and elastic modulus of Mo–Al–N films first increased and then decreased with increasing Al content in the films and the highest values were 32.6 GPa and 494 GPa, respectively, at 3.7 at.% Al. The films with an Al content in the range between 4.1 at.% and 9.5 at.% were found to be optimized for wear resistance applications, which showed low average friction coefficient values of 0.31–0.35 and wear rate of 3.6 × 10−9–8.1 × 10−9 mm3/Nmm.