Investigation on anti-wear properties of sulfide layer on bearing steel lubricated by oil-containing FeS particles

To enhance the anti-wear properties of the sulfide layer on the surface of 52100 steel under harsh conditions, FeS particles were mixed into the oil as additive. The anti-wear properties of plain surface and sulfurized surface under base oil and oil-containing FeS particles lubrication were investigated by a ball-on-disk tester. The composite effects of sulfide layer and FeS particles with different sizes and amounts in base oil were studied as well. The results showed that the anti-wear properties can be improved for sulfurized and plain steel surfaces after FeS particles were used as additive in oil. The composite effect of sulfide layer and FeS particles possessed very good anti-scuffing and anti-wear properties. The FeS particle could supplement the loss of sulfur from the sulfide layer in the wear process, so that the service life of FeS film can be prolonged under more harsh conditions. An appropriate addition amount of FeS is important for the composite effect.