Mechanical Properties and Oxidation Behavior of Cr–Si–N Coatings

Cr–Si–N coatings were prepared through reactive direct current magneton sputtering using a high N2/Ar flow ratio of 1. The addition of Si to improve the mechanical properties and oxidation resistance of Cr–N coatings was examined. The results indicated that the Cr–Si–N coatings with an Si content of <12 at % and an N content of >50 at % exhibited a cubic CrN phase with a columnar structure, whereas the coatings with 14 at % Si comprised of a nanocomposite structure, and the coatings with 16–18 at % Si were near-amorphous. The nanocomposite Cr32Si14N54 coating possessed hardness and Young’s modulus values of 17 and 209 GPa, respectively, accompanied with a hardness to effective Young’s modulus (H/E*) value of 0.077 and an elastic recovery (We) level of 55%—all the properties were highest within the as-deposited coating. The addition of Si was also beneficial to reduce the surface roughness and improve the oxidation resistance.