Humphrey, Ed Morris, Nick Leighton, Michael Rahmani, Ramin Rahnejat, Homer Multiscale friction in lubricant-surface systems for high performance transmissions under mild wear The lubricant-surface system is complex in nature and can significantly affect the frictional performance of high-performance transmission systems. The complexity stems from the coupled mechanical and chemical phenomena that occur at the interfacial tooth conjunctions. A combined analytical and precision experimental approach is presented to analyse the salient parameters of the lubricant-surface system. A multiscale procedure comprising topographical measurement, pin-on-disc tribometry, atomic force microscopy in lateral force mode, X-ray photo-electron spectroscopy and continuum contact mechanics analysis under mixed non-Newtonian thermo-elastohydrodynamics is used to describe the formation of a tribo-film, as well as wear and frictional characteristics of the lubricant-surface system. The contribution of chemisorbed and physisorbed bonded tribo-film on the boundary coefficient of friction is ascertained at different physical scales. Therefore, the paper presents a novel multiscale analysis, promoting improved understanding of the complex interactions between mechanisms of friction, wear and surface chemistry. Gear;Tribo;Film;Additive;ZDDP;AFM;Atomic force microscopy;Wear;Friction;Mechanical Engineering not elsewhere classified;Mechanical Engineering 2018-06-06
    https://repository.lboro.ac.uk/articles/journal_contribution/Multiscale_friction_in_lubricant-surface_systems_for_high_performance_transmissions_under_mild_wear/9570257