Mechanism of friction of fullerenes

In the past few years, inorganic fullerene‐like (IF) supramolecules of metal dichalcogenide WS₂ and MoS₂ with structures closely related to (nested) carbon fullerenes and nanotubes have been synthesized. Recent experiments showed that IF added to oil and impregnated into the porous matrixes possess lubricating properties superior to those of layered WS₂ and MoS₂ (2H platelets). The main goal of this work was to analyze the mechanism of friction of fullerene‐like nanoparticles. Friction and wear behavior of IF in different contact conditions is studied. Third body model is considered. Sliding/rolling of the IF nanoparticles in the boundary of the first bodies and in between the wear particles (third body) is supposed to facilitate the shear of the lubrication film. Broken and oxidized 2H‐WS₂ small pieces adhered to wear debris do not provide high tribological properties especially under high loads.