Tribological Properties And Mechanism Of Non-active Envinorment-friendly Additive

In light of the increasing severity of environmental regutions, automakers and lubrication marketers are facing more and more challenges. Gasoline Vehicles are now equipped with three-way catalytic converters to control emissions of HC, CO and NOx; Diesel vehicles are now equipped with exhaust gas recirculation (EGR) ystems and particulate traps. The use of these emission control decices demands engine oils with lower phosphorus and sulfur content. Thus, there is some urgency in lowering the treat level of zinc dialkyl dithiophosphate (ZDDP) in modern engine oils. Besides emission control, fuel economy and long life are also becoming key drivers of new engine technology and engine oil upgrades.The developmental trends of industrial lubricant are to enhance the thermal oxidative stability, to prolong the using period of oil and to save energy. Based on the above trends, the additives for industrial lubricants come forth some new requirements, for example, employing new type additive containing boron.Their tribological performances were systematically evaluated by using a four-ball machine. The tribological properties of the synthesized MCC alone and their synergistic effects with ZDDP were studied and compared with that of ZDDP alone in API-â…¡mineral base oil (5CST); the effect of adding into amine on the tribological properties are studied by using a four-ball machine in 5 CST. Their action mechanism was investigated by the combination of SEM and XPS surface analysis technologies and more sensitive XANES methodology. Some valuable results were obtained as follows:1. Phosphorus-free and sulfur-free organic molybdate ester (ME) possesse excellent anti-wear and friction- reducing properties. The antiwear and friction-reducing properties of sulfur-containing triazine aminomethyl derivatives are better than that ofZDDP. while their load-carrying capacity is worse than that of ZDDP.The synthesized triazine derivatives and ZDDP show excellent synergistic tribological behavior in 5CST. It is found that four kinds of them can partially replace ZDDP by at least fiftyt percent.2. The loading-carry capability of borate ester containing no active element is relatively weak. When amine and borate ester form BN coordination bond, the loading-carry performance of the complexes become worse compared base oil. However, BN ammonium complex can improve the loading-carry performance of base oil. Under relatively low load, borate ester containing no active element has slightly antiwear property, and its antiwear performance can be improved when BN coordination bond or BN ammonium formed.