Nm Of Ceo <sub> 2 </ Sub>, Of Tio <sub> 2 </ Sub> Particle Composition As The Tribological Properties Of Lubricating Oil Additives And Mechanism

As the development of our economy,our country is needing more and more high quality lubricanting oils and lubricanting oil additives.The traditional oil-soluble anti-wear and friction-reducing additives which contain harmful elements such as sulfide,chlorine and phosphorus have not met the needs of development of modern industry for the poor qualities of lubricant products and rising consciousness of environment protection.So they will be fallen into disuse. The routine micron inorganic particles can抰be dispersed in the oil,and can scratch the working surfaces,so they are not be used widely.In this condition, many lubricant companies,academes and college schools are searching new breaks to meet the needs.As the development of nanotechnology,nano-lubricant additives will give a bright future of resolving the problems well.In this paper,nano-particles of CeO₂ and TiO₂ were selected appropriately,the surfaces of nano-particles of CeO₂ and TiO₂ were modified with surfactants,nano-lubritanting oils were prepared by putting nano-particles of CeO₂ and TiO₂ into base oil,the nano-lubricanting oils were tested on a four-ball tribotester and the anti-wear and friction-reducing mechanisms of nano-particles of CeO₂ and TiO₂ as lubricanting oil additives were studied with modern testing tools.The main conclusions are following;1.The crystal structure and average sizes of nano-particles of CeO₂ and TiO₂ were tested by a X-ray Diffractometer.And the morphologies and average sizes of nano-particles of CeO₂ and TiO₂ were measured with a Transmission Electron Microscope.The results indicated that nano-particles of CeO₂ whose diameters are about 10.4nm appeared as spherical powders and nano-particles of TiO₂ whose diameters are about 15.2 nm appeared as granular particles.2.On the basis of HLB values,suitable surfactants such as Tween-20, Tween-60,Span-20 and sodium sodecylbenzenesulfonate were selected to modify the surfaces of nano-particles of CeO₂ and TiO₂.The results indicated that nano-particles of CeO₂ and TiO₂ have the good dispersion and stability in the lubricating oils after modification when the qualitatively proportion of surfactants is 2;2;1;1.3.Tribological properties of nano-particles of CeO₂ and TiO₂ as lubricanting oil additives were tested on a four-ball tribotester.The results implied that nano-additives of CeO₂ and TiO₂ can improve the tribological properties of the lubricating oils by rising P_B and reducing WSD andμ.4.The optimal proportion of nano-additives of CeO₂ and TiO₂ as lubricanting oil additives is Wt_CeO2;Wt_TiO2=1;3,and the content is about 0.6%。5.Through observing the examples of nano-lubricanting oils and the morphologies of the worn steel balls and analyzing experimental datum,the results could imply that the compound surfactants encircled the nano-particles and they formed many microcapsules in the lubricating oil,so the nano-particles of CeO₂ and TiO₂ could disperse well and not reunite again.It might also be that nano-particles of CeO₂ could restrain the reunification of nano-particles of TiO₂.6.By using modern testing tools,such as TEM,X-ray diffractometer and SEM, the mechanisms of anti-wear and friction-reducing of nano-particles of CeO₂ and TiO₂ as lubricanting oil additives were discussed according to crystal structures, sizes of nano-particles and the morphologies of worn steel balls.Some mechanisms could be揗inute Ball Bearing Effect Mechanism?揗inute Polishing Effect Mechanism?揊illing and Repairing Effect Mechanism ?and搕he Compound Effect Mechanism?This paper was a groping study of揘anometer Material抯Application in Lubricanting Technology?and it is one part of揜esearch on the Key Techniques of Industrialization of Nanometer Materials as Lubricanting Oil Additives(05FZ31)" and揜esearch on Nanometer Material抯Application in Engine Lubricanting oil (06FZ008)?of Shanghai Scientific and Technological Committee.More research works are expected to be further developed.