Optimum MoS2–Cr coating for sliding against copper, steel and ceramic balls

The chromium doping in MoS2–Crx% coatings improves their mechanical properties, adhesion strength and tribological properties. An investigation of the coating system MoS2–Crx% with varying chromium contents deposited on tungsten carbide disks by unbalanced magnetron sputtering was carried out. The results of hardness, elastic modulus, scratch adhesion and tribological properties of these coatings were reported. The tribological properties of the coatings against copper, AISI 52100 steel and Si3N4 ceramic balls were investigated by using an oscillation sliding test machine with a point-contact wear mode under dry condition. A Cr metal atomic percentage at 8% in the MoS2–Crx% coating was found to possess the optimum wear resistance and durability when paired with a copper, steel and ceramic ball.