Study On The Synthesis And Tribological Performances Of Organic Tungsten Additives

Four series of lubricating oil additives—tungsten (alkyl) larylamino dithophosphoric were synthesized. Their soluble stability and copper corrodibility were studied, and their tribological performance in three base oil with different mass fractions and loads were evaluated on a four-ball tester, the optimum synthesized way was determined and an efficiency lubricant antiwear additive was synthesized(NSND-7). Then the worn steel surface was analyzed by JSM-6360LV vacuum scanning electron microscopy (SEM) and Falcon energy dispersive spectrometer (EDS). The tribochemistry principle of NSND-7 was also discussed. The results showed that NSND-7 had good soluble stability and anti-corrosion and tribological performance in three base oils, and when NSND-7 with concentration 1.0wt%, the PB value of three APIⅠclass base oils 150,250 and 500 could be increased by 92%,104% and 108%, respectively, meanwhile, the wear scar diameter (WSD) of steel ball could be reduced by 25.8%,37.8% and 41%. In the course of friction, NSND-7 could form FeS reaction film and WS2 aggradation film on the surfaces of friction pairs, which were able to reduce the direct contact between friction pairs and improve the base oil's anti-pressure, anti-wear performances effectively.