Adsorption of ATF additives on wet clutch friction interfaces under water contaminated lubricant conditions
2014 (English)Conference paper, Presentation (Refereed)
Stable friction and positive slope of friction-speed is the typical criterion for a good clutch performance. Lubricated friction interfaces used for wet clutches produces different friction behavior depending on the lubricant conditions. Usually the lubricant conditions vary for different automatic transmission fluid (ATF) formulations implying e.g. water contamination and these conditions might influence the deterioration of the clutch plates. The aim of this paper is to verify additive adsorption on friction interfaces and ageing of the friction material in wet clutch system for a water contaminated commercial ATF (DEXRON® VI). Standard clutch plates are employed in an automated wet clutch test rig to evaluate the friction characteristics of the tested lubricant. For controlled test conditions (speed, contact pressure, oil temperature) and specific number of test cycles, the mean friction coefficient and the friction vs. speed relations are monitored during sliding test. The resultant tribofilms on the tested friction interface surfaces are characterized by means of Scanning Electron Microscopy-Energy Dispersive X-ray spectroscopy (SEM- EDS), Attenuated Total Reflectance -Fourier Transform Infrared Spectroscopy (ATR-FTIR) and X-ray Photoelectron Spectroscopy (XPS analysis). The spectroscopic techniques were used to analyse adsorbed additives on friction interfaces and made it possible to correlate measured data to the specific friction behavior obtained after water contamination of the ATF.
Place, publisher, year, edition, pages
Research subject Machine Elements; Chemical Technology
IdentifiersURN: urn:nbn:se:ltu:diva-37182Local ID: b1e7f3db-edc4-4dc7-bd7c-65a5869a3044OAI: oai:DiVA.org:ltu-37182DiVA: diva2:1010680
Nordic Symposium on Tribology : 10/06/2014 - 13/06/2014
Godkänd; 2014; 20140616 (nowfat)2016-10-032016-10-03Bibliographically approved