Microstructure and water-lubricated friction and wear properties of CrN(C) coatings with different carbon contents

► CrN(C) coatings with different C content were synthesized on 316L stainless steel. ► The hardness of CrN(C) coatings deposited at 1 A increased to 22.5 GPa. ► The sp2CN, sp3CN and CrC bonds were formed in CrN(C) coatings. ► The CrN(C) coatings deposited at 1 A exhibited the lowest friction coefficient. ► The CrN(C) coatings lowered the wear rates of Si3N4 balls compared with CrN coatings.