IN SITU RAMAN MICRO SPECTROMETRY INVESTIGATION OF A DYNAMIC CONTACT LUBRICATED WITH NANOPARTICLES DISPERSED IN BASE OIL: STUDY OF NANOPARTICLES TRANSFORMATIONS DURING THEIR TRANSIT THROUGH THE TRIBOLOGIC INTERFACE

摘要

The additivation strategies using nanoparticles developped during the last decades are at the origin of extensive studies in order to understand the action mechanisms of nanoparticles in the friction and wear reduction processes. As far as Raman micro spectrometry is a powerful technique for physical and chemical in situ analyses in a dynamic contact, the technique is used, in the present study, to characterize the pressure and lubricant film thickness distributions and to follow the liquid/solid concentration evolution existing in a purely sliding sphere on plane contact lubricated with exfoliated graphite nanoparticles in dispersion in 5P4E. The careful examination of the Raman bands characteristic of the nano-particles in the point spectra recorded across the contact area allowed us to follow their structural evolution during their transit through the sliding interface.