Sulfide layers with a certain thickness were made on the surface of 1045 and 52100 steels by means of low temperature ion
sulphuration process. Metallography, SEM +EDX and XRD were adopted to analyze the structure of layers, the tribological properties of layers lubricated by paraffin oil were also investigated on a SRV reciprocating tester. The results showed that sulfide layer was loose, its surface was porous and its structure was composed of FeS, FeS2 and substrate phases. Sulfide layer possessed a remarkable
friction-reducing effect, its friction coefficient was about 50% lower than that of the surface without layer. With the increase of layer thickness, its friction coefficient was unchanged basically, and under low load conditions, its endurance life was prolonged, but showed little changes under high load conditions. Under the same experimental conditions, the endurance life of sulfide layer on 52100 steel was longer than that on 1045 steel and the friction coefficient was a little lower.