Synthesis And Tribological Performance Study Of Lubricant Additives

Lubricant additives have developed from meeting the demands of the motor requirements in initial stage , to adjusting to the different working conditions ,and then transiting to widely adapt to today's needs of environmental protection and energy saving .As green lubricant additives ,they'll not only have a good response in the base oil ,but also be no harmful to the ecological environment .In recent years ,researching and development on new type ,multi-functional and environmentally friendly lubricant additives have become the focus study to tribological scholars.Based on this point ,three kinds of clean ,pollution-free lubricant additive products had been prepared in this paper .Namely ,anti-wear and friction-reducing additives—nitrogen-containing borate BNH and BNO ,organic metal additive—8-hydroxyquinoline Fe(â…¢) .The products were characterized and analyzed by IR ,1HNMR ,XRD ,TEM and other modern testing technologies .We sincerely expect to provide some synthetic experimental basis for the study of green environmental-protection additives .The as-prepared BNH and 8-hydroxyquinoline Fe (â…¢) were scattered to the liquid paraffin (LP) by mass fraction gradually increased and investigated tribological performance on four-ball tribometer .We obtained a series of much more excellent experimental data .According to the test results :at the optimum addition amount ,1.0 % for BNH and 1.0 % for 8-hydroxyquinoline Fe (â…¢) ,the two additives showed the best anti-wear and friction-reducing properties ,respectively .Apart from above mentioned ,the performance study of the compounded system composed of heterocyclic derivatives and inorganic nanoparticles is of great practical significance .So as to accumulate data for practical application and search for the best formula of combinational additives .From this perspective , we tried to complex the two as-prepared additives and investigated the tribological performance of compounded system containing BNH and Fe₃O₄/OA .The results showed that the anti-wear and friction-reducing abilities of the mixture were much better than that of single dose .We had obtained the best anti-wear and friction-reducing synergistic effect at the proportion of 1.0 % BNH : 0.25 % Fe₃O₄/OA .At this addition ,the friction coefficient and WSD were reduced 22.9 % and 5.1 % comparing to 1.0 % BNH single dose ,0.027 and 0.37 mm respectively ;While this mixture was used as a extreme pressure lubricant ,the addition of Fe₃O₄/OA should be appropriately increased (more than 2.5 %) .The morphologies of the rubbed surfaces of the steel balls after wear test were investigated and the friction mechanisms were briefly discussed .The nitrogen-containing heterocyclic borate decompose under the frictional heat in the friction process and the active elements of N ,B in borate react with friction pairs and then the adsorbed film or tribochemical film with surface-enhancing and good anti-wear ,extreme pressure properties is formed .The lubricating effect of 8-hydroxyquinoline Fe (â…¢) may be due to that the complex nanorods play a similar "micro-bearing" role in friction interfaces .In addition ,under the high temperature and high pressure conditions ,the complex decomposition and the formation of metal protective layer play an important role in improve its tribological properties.