Friction and wear of bronze powder composites including fullerene-like WS2 nanoparticles

In the past few years, WS2 and MoS2 nanoparticles (IF) with structures closely related to (nested) carbon fullerenes and nanotubes have been synthesized. It was shown before that addition of a small amounts of such nanoparticles to lubricating fluid largely improve the tribological properties of contact surfaces. In the present work, impregnation of the nanoparticles into a porous powder (bronze–graphite) matrix is demonstrated. The critical point to seizure of the powder matrix impregnated with mineral oil, 2H–WS2 platelets and IF nanoparticles was measured and is 300, 570 and 950 N, respectively. The friction coefficient of the powder matrix lubricated by oil and oil+IF-WS2 was measured. It was found that the addition of the IF nanoparticles in the oil decreased the friction coefficient by 30–50% as compared to the surfaces lubricated by the oil alone.