Microstructure and tribological performance of (AlCrWTiMo)N film controlled by substrate temperature

Abstract The (AlCrWTiMo)N films were deposited at different substrate temperatures by magnetron sputtering. The microstructures, mechanical properties and tribological performances of the (AlCrWTiMo)N films were investigated. Results showed that the deposition rate and nitrogen content of the film decreased slightly with the increase of the substrate temperature. From the interlayer surfaces to the film surfaces, the films showed gradient structures, which gradually transformed from amorphous to nanocrystalline. With the increase of the substrate temperature, the width of the amorphous region decreased, and the width of the nanocrystalline region increased. The top nanocrystalline regions were typical face-centered cubic (FCC) structures. The grain size and surface roughness of the film decreased gradually with the increase of the substrate temperature. The critical load (LC1), hardness and elastic modulus of the film increased first and then decreased, and reached the maximum value when the substrate temperature was 200 ℃, which were 16.06 N, 24.5 GPa and 263 GPa, respectively. The friction coefficient and wear rate of the film decreased first and then increased, and reached the minimum value at substrate temperature 200℃, which were 0.71 and 1.1 × 10−5 mm3/Nm, respectively. The wear mechanism of film was mainly abrasive wear accompanied by mild fatigue wear.