Keywords

Boundary Lubrication, EHL Film Geometry, Lubricant Chemical Analysis, Fluorescence, In situ Fluorescence in Tribologic Contacts

Track

In Situ Tribology II: Material Tribology and Tribotesting Joint Session (Session 3B)

In Situ Fluorescence Microscopy Applied to Dynamic Lubricated Contact Investigations 

Raman microspectrometry technique is a powerfull method to investigate both physical and chemical conditions existing in a dynamic tribologic interface. The main limitations of such a technique is its low sensitivity due to the tiny intensity of the raman spectra. In order to overcome these limitations fluorescence microscopy is used to characterize the lubricant film thickness distribution profile in the case of various lubricating liquids. For this purpose a molecular probe constituted by a dye (rhodamine B) is dissolved in the studied liquid at a low concentration (0.1%) to avoid rheological modifications. Fluorescence point spectra (laser probe diameter ≈ 5μm) are recorded. The elongated shape of the laser probe allows us to linearly relate the intensity of the fluorescence band intensity to the lubricant film thickness. Due to the high intensity of fluorescence compared to Raman spectrometry, the acquisition times are shorter and the thickness detectable limit is improved.

Authors and Company/Institution

J. Mansot and A. Molza, GTSI, Université des Antilles et de la Guyane,Pointe à Pitre, Guadeloupe,
M. Adoue and Y. Bercion, C3MAG, Université des Antilles et de la Guyane, Pointe à Pitre, Guadeloupe