Tribological Behavior of Self-Lubrication Bearing Materials of Steel-Copper-Polyoxymethylene Containing MoS2-IC Nanoparticles

Intercalation compound of polyoxymethylene into molybdenum disulfide nanoparticles (POM/MoS₂-IC) were prepared from trioxane, dioxolane and restacked exfoliated-MoS₂. The so prepared nanocomposite was used as the plastic layer of self-lubrication bearing materials of steel-copper-POM. Pure POM was also selected as a comparative sample. Tribological behaviors of the obtained samples were studied on an end-face tribometer. Wear scar surfaces of the two plastic layers were characterized by a field emission scanning electron microscope. The elements of the counterpart steel surface were investigated by X-ray photoelectron spectroscopy. Results showed the wear surface of steel-copper-pure polyoxymethylene consisted of deep furrows, large-area scars and obvious flow marks. However, self-lubrication bearing materials of steel-copper-polyoxymethylene containing MoS₂-IC nanoparticles presented excellent friction reduction and wear resistance especially under high loads. POM/MoS₂-IC nanoparticles and its tribochemical resultants restrained the plowing effect of the counterpart steel on the plastic layer through forming a transferred film on the counterpart friction surface.