Performance and mechanisms of silicate tribofilm in heavily loaded rolling/sliding non-conformal contacts. (July 2018)

• Record Type: Journal Article
• Authors: Hansen, Jonny; Björling, Marcus; Minami, Ichiro; Larsson, Roland
• Is Part Of: Tribology international. Volume 123(2018)
• Page Start: 130
• Page End: 141
• Publication Date: 2018-07
• Subjects: Elasto-hydrodynamic -- EHD -- Boundary film -- Surface analysis; Tribology -- Periodicals; 621.89
• DOI: 10.1016/j.triboint.2018.03.006
• Languages: English
• ISSNs: 0301-679X

Abstract

Abstract: Lubricant performance is vital as heavy-duty gear manufacturers increase power density in their efforts towards increased efficiency. In this work, a recently developed ionic liquid is introduced as a multifunction additive for use in hydrocarbon base fluid. A ball-on-disc tribological test machine was used to evaluate friction and wear in heavily loaded mixed rolling/sliding conditions. The novel multifunctional additive is benchmarked against conventional axle-gear oil additives, and results shows excellent tribological performance in terms of friction and wear. Post-test surface analysis of the wear scars revealed a silicate based tribofilm derived from the novel ionic additive, contrary to conventional phosphorous and/or sulfur based. The silicate tribofilm is correlated to a significantly increased wear resistance and vastly improved running-in performance. Graphical abstract: Image 1 Highlights: A novel additive is evaluated in conditions relevant to heavy-duty gears. Tribo-performance in heavily loaded mixed rolling/sliding conditions was excellent. Improved friction and wear performance is attributed to a novel silicate tribofilm.