Liñeira del Río, José ManuelFernandes, Carlos M.C.G.Gonçalves, David E.P.Seabra, Jorge H.O.2024-12-102024-12-102024-07-18Tribology International Volume 199, November 2024, 110007https://hdl.handle.net/10347/38066In response to the mounting concern over environmental pollution and the depletion of petroleum reserves, biolubricants have emerged as a promising alternative to mineral oil-based lubricants. Thus, the aim of this research is the tribological characterization of green castor and soybean nanolubricants containing functionalized CaCO3 nanoparticles. Friction improvements were reached with maximum friction decreases of 14 % and 18 % compared to castor and soybean oils. Concerning wear, optimal concentration for castor and soybean nanolubricants was intermediate concentration of 0.15 wt% with width wear reductions of 27 % and 24 % compared to castor and soybean oils, respectively. Tribological mechanisms of tribofilm formation, repairing and rolling-bearing were identified. In rolling-sliding tests, the use of nanoparticles was crucial at low speeds with outstanding friction reductions.eng© 2024 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY licensehttp://creativecommons.org/licenses/by/4.0/BiolubricantsNanoparticlesFunctionalizationSurface analysisjournal article10.1016/j.triboint.2024.110007open access