20.500.12556/RUL-129017 Elasto-hydrodynamic friction changes on steel surfaces arising from the modified surface energy of the steel due to additive boundary films The effect of three different film-forming additives mixed in PAO oil on the elasto-hydrodynamic (EHD) friction was investigated and compared to cases with the base oil only. When the boundary films were formed on the surfaces, the organic friction modifier (OFM) decreased the EHL friction by up to 8.7%, the ionic liquid (IL) decreased it by up to 6.4%, while the polymeric organic friction modifier (pOFM) increased it by up to 4.2%. In contrast, if the boundary films were not formed, the EHL friction remained the same as with the base oils only. The oils` surface tension and viscosity were analysed at 25 °C and 100 °C as potential influencing effects, and the most important parameter for friction changes was found to be the surface energy. The mechanism behind this EHL friction reduction is, therefore, the effect of the boundary films on the poor oil-surface wetting and the consequent boundary slip. This study confirms the poor wetting arising from additive boundary-film formation as a relevant EHL friction-reduction mechanism. This observation is similar to that observed previously for surface coatings, thus suggesting that the boundary films of the surface-energy-reducing additives is a parameter with the potential to reduce the EHL friction. elastohydrodynamic lubricant additive traction wetting elastohidrodinamika aditivi za maziva trenje omočljivost true false true Angleški jezik Slovenski jezik Članek v reviji 2021-08-24 08:20:48 2021-08-24 08:20:55 2025-03-11 11:47:27 0000-00-00 00:00:00 2021 0 0 Str. 1-10 Vol. 164, art. 107203 Dec. 2021 0000-00-00 PostprintKoncna Objavljeno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 2023-07-24 531.43:669.14:544.722.3 0301-679X 10.1016/j.triboint.2021.107203 73795843 RAZ_Polajnar_Marko_2021.pdf RAZ_Polajnar_Marko_2021.pdf 1 0320362DE79294BF00CAB4EE83B50D11 de6d81735b8c7591a7b05efdabe5f7197d0770f6f8a201798e9315e8a30e2f0c 97c009ec-04a5-11ec-a523-00155dcfd717 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=145935 https://www.sciencedirect.com/science/article/pii/S0301679X21003510 1 38933aee-04a3-11ec-a523-00155dcfd717 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=145934 Fakulteta za strojništvo 0 0 0