A study on the microstructures and mechanical properties of pulsed DC reactive magnetron sputtered Cr–Si–N nanocomposite coatings

The nanocomposite Cr–Si–N thin films with various Si contents have been prepared by a bipolar asymmetric pulsed DC reactive magnetron sputtering system. The Cr–Si–N coatings exhibit a mixed CrN and Cr2N phases when Si contents is lower than 3.1 at.%, whereas a single CrN phase is observed for coatings with higher Si content. The crystallite size of Cr–Si–N decreases with increasing Si content and reaches to a minimum of 5.2 nm when the Si content is 10.1 at.%. A high hardness, low friction coefficient and good nanowear resistance are found in the Cr–Si–N coatings with around 10.1 at.% Si in this work.