Tribology Online
Online ISSN : 1881-2198
ISSN-L : 1881-218X
Article
Correlation between Tribofilm Formation and Friction Coefficient in Continuously Variable Transmission at the Initial Stage of Rubbing
Ayako Omura Atsushi KorenagaHiroki ManoTsuguyori OhanaAkira SugimuraAkira MizunoYoshiyuki TanakaMakoto MaedaKazumasa Uchida
Author information
JOURNAL OPEN ACCESS

2019 Volume 14 Issue 4 Pages 208-213

Details
Abstract

To improve the transmission efficiency of a continuously variable transmission (CVT) system, it is effective to form a tribofilm with higher friction coefficient. Therefore, understanding of the correlation between the tribofilm formation and friction coefficient in a CVT fluid has been a great deal. In this study, the tribofilm formation on a bearing steel ball surface under the simulated additive oil was investigated. We used ball-on-disk tribological test and optical microscopy imaging to observe the temporal changes in the tribofilm growth. Atomic force microscopy and energy-dispersive X-ray spectrometry analyses revealed that the tribofilm consisted of pad-like structures derived by tricresyl phosphate and calcium sulfonate additives. A binary imaging analysis showed that the total area of the pad-like structure was a key parameter determining the friction coefficient. The pads were repeatedly desorbed and reformed during the sliding test. These results improve the design of future CVT systems and lubricants.

Content from these authors
© 2019 by Japanese Society of Tribologists

This article is licensed under a Creative Commons [Attribution-NonCommercial-NoDerivatives 4.0 International] license.
https://creativecommons.org/licenses/by-nc-nd/4.0/
Previous article Next article
feedback
Top