Microstructure and tribological behavior of TiAlSiN coatings deposited by deep oscillation magnetron sputtering

Development of pulsed‐techniques aimed to generate highly ionized target species and high plasma density opens up a new way to tailor composition, structure, and properties of coatings. In this work, TiAlSiN coatings have been deposited at various negative substrate biases ( V s ) using deep oscillation magnetron sputtering by sputtering a TiAlSi compound target in Ar/N 2 mixtures. The increase in V s from −30 to −120 V resulted in a decrease in (111)‐preferred orientation and grain size, together with the increase in residual stress and rough morphology. The nc‐TiAlN/a‐Si 3 N 4 nanocomposite structure was obtained in coatings. The highest hardness and Young's modulus reached 42.4 and 495 GPa at −120 V, respectively. However, at −60 V, the coatings with the highest H/E* and H 3 /E* 2 ratios of 0.095 and 0.332 exhibited excellent adhesion with above HF 1 level, the lowest coefficient of friction ( COF ) of 0.35 and specific wear rate of 2.1 × 10 −7 mm 3 N −1 m −1 . Wear mechanism changed from the mixture of severe adhesive, oxidative and abrasive wear to mild oxidative wear to severe oxidative wear. TiAlSiN coatings with high hardness and H/E* and H 3 /E* 2 ratios exhibited the decrease in COF and wear rate due to refined grains in uniform distribution, which well promoted oxide layers formed on sliding contact surface.