Microstructure and Tribological Properties of Plasma-sprayed Nanostructured Sulfide Coating

摘要

The friction and wear properties of plasma-sprayed nanostructured FeS coating were investigated on an MHK-500 friction and wear tester under both oil lubrication and dry friction condition. The microstructure, worn surface morphology and phase composition of the coating were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). It was found that the coating was mainly composed of FeS, a small quantity of Fe_(1-x)S and oxide were also found. The coating was formed by small particles of 50-100 nm in size. The thickness of the coating is approximately 150 mu m. The friction-reduction and wear-resistance properties of plasma-sprayed nanostructured FeS coating were superior to that of GCrl5 steel substrate. Especially under oil lubrication condition, the friction coefficient of nanostructured FeS coating was 50 percent of that of GCrl5 steel, the wear scar widths of the coating were also reduced to nearly 50 percent of that of GG15 steel under high load. The failure of the coating was mainly attributed to plastic deformation under both oil lubrication and dry friction condition.