Tribological behavior of Si₃N₄-Ti₃SiC₂ contacts lubricated by ionic liquids

The tribological behavior of Si₃N₄-Ti₃SiC₂ contacts lubricated by ionic liquids (ILs), L-B106 and L-P106, were investigated on an Optimol SRV oscillating reciprocating friction and wear tester. As the results, L-P106 and L-B106 showed good tribological behavior comparable to Glycerol under a load of 20 N at room temperature. L-P106 showed the best antiwear and friction-reduction ability under the load of 100 N at both 25°C and 100°C. The elemental composition and chemical nature of the boundary films generated on worn Ti₃SiC₂ surface were analyzed on a scanning electron microscope with a Kevex energy dispersive X-ray analyzer attachment and X-ray photoelectron spectrometer. It indicates that tribochemical reactions of the ILs with Ti₃SiC₂ surface occurred during the sliding process. TiO₂, SiO_x and complicated Ti-containing compound likely TiF₄ and Ti(BO₂)₄ or Ti₃(PO)₄ boundary film were formed on the worn Ti₃SiC₂ surface, which enhanced the antiwear and friction-reduction ability of the Ti₃SiC₂ surface.