Structure, corrosion, and tribological properties of CrSiN coatings with various Si contents in 3.5% NaCl solution

The CrSiN coatings with different silicon contents were deposited on 304L stainless steel and single silicon substrates using medium frequency magnetron sputtering via adjusting the silicon target current. Microstructures, mechanical, corrosion, and tribological performances were systematically investigated by the corresponding equipment. The results showed that the CrSiN coatings were composed of 2 phases: the nanocrystalline CrN coordinated with adjacent Si 3 N 4 to form a typical nanocrystalline amorphous structure. With the increase of silicon content, the hardness emerged a rising trend until 12.65 at.%, where the hardness reached its highest value at approximately 22 GPa. At the moment, the friction coefficient and wear rate were approximately 0.27 and 6.9 × 10 −8 mm 3 /Nm, respectively, which were 18.75% and 61.67% lower than that of the CrN coating, respectively. This mainly attributed to the lubrication of tribochemical products of SiO 2 and Si(OH) 4 . In addition, excellent toughness, high hardness, preferable adhesion, and good corrosion resistance also contributed to improve the tribological properties of CrSiN coating.