A S-containing additive, sulfuration modified rapeseed oil (named as SRO), was prepared by chemical modification of rapeseed oil with sulfur compounds. The results indicate that the friction and wear of the magnesiu...A S-containing additive, sulfuration modified rapeseed oil (named as SRO), was prepared by chemical modification of rapeseed oil with sulfur compounds. The results indicate that the friction and wear of the magnesium alloy-steel tribomates could be effectively reduced by formulating SRO into rapeseed oil lubricant. The friction coefficients and the wear volumes of magnesium alloy decrease with increasing contents of SRO. The surface lubricated with SRO-doped rapeseed oil was characterized by less wear as compared with that lubricated with neat rapeseed oil. The enhanced anti-wear and friction-reducing abilities of rapeseed oil by SRO in the lubrication of magnesium alloy against steel were ascribed to the formation of a composite boundary lubrication film due to the strong adsorption of SRO and rapeseed oil onto the lubricated surfaces and their tribochemical reactions with magnesium alloy.展开更多
Neodymium dialkylthiophosphate (NdDDP) with alkyls of isopropyl and isooctyl were synthesized by exchanged reaction respectively. The structures of the two NdDDPs were determined using IR and XRD. Properties of anti...Neodymium dialkylthiophosphate (NdDDP) with alkyls of isopropyl and isooctyl were synthesized by exchanged reaction respectively. The structures of the two NdDDPs were determined using IR and XRD. Properties of anti-wear and friction-reducing of the two additives were investigated with four ball experiment and the commercial anti-wear additive ZDDP was selected as control. The elemental analysis of the wear scars after 10 s friction at low stress were investigated by EDXA (Energy Dispersion Analysis of X-ray). Primary results showed that the NdDDPs possess better lubrication ability than ZDDP. This might mainly be contributed to the formation of a boundary film containing Nd2O3, FeS and sulphate, phosphate, organo-sulfide, etc., and a neodymium-rich diffused layer which changes the crystal structure of the surface of friction materials.展开更多
Considering electromagnetic effect when investigating tribological properties of rapeseed oil is benefical not only to the improvement of green lubrication, but also to the development of tribology theories and practi...Considering electromagnetic effect when investigating tribological properties of rapeseed oil is benefical not only to the improvement of green lubrication, but also to the development of tribology theories and practices. In the present paper, the tribological properties of rapeseed oil under different intensity of electromagnetic field and normal loads were evaluated on a modified tribo-tester. The results indicated that the electromagnetic field could improve the anti-wear and friction-reducing property of the rapeseed oil. Furthermore, the influencing mechanisms were discussed from the perspective of electromagnetism according to the analytical results of SEM, EDS and XPS techniques.展开更多
Cu-doped muscovite(Mu) composite particles, abbreviated as Mu/Cu, were prepared via liquid phase reduction method. The morphologies, phase composition and elementary distribution of the as-prepared Mu/Cu and raw mus...Cu-doped muscovite(Mu) composite particles, abbreviated as Mu/Cu, were prepared via liquid phase reduction method. The morphologies, phase composition and elementary distribution of the as-prepared Mu/Cu and raw muscovite particles were characterized by means of scalmmg electron microscope(SEM), X-ray diffraction(XRD) and energy dispersive spectrometry(EDS). The tirbological properties of Mu/Cu and Mu as lubricant additives in lithium grease were evaluated on a block-ring tribomachine. The roughness, 2D and 3D morphologies and elementary distribution of block worn surface were analyzed to explore the tribogical mechanism. The results show that muscovite are evenly coated by the cubic Cu nanoparticles in composite particles. Both Mu/Cu and Mu can effectively improve the tirbological properties of lithium grease and Mu/Cu exhibits better tribological performance than Mu. The friction coefficient of Mu/Cu is decreased by 69.2% as compared to that of lithium grease. The layer structure of muscovite is synergistic with Cu nanoparticles in contribution to the formation of lubricant film mainly consisting of O, Si, Fe, Cu as well as Al elements on the block worn surface thereby further reducing the friction and wear.展开更多
基金Project (50975282) supported by the National Natural Science Foundation of China
文摘A S-containing additive, sulfuration modified rapeseed oil (named as SRO), was prepared by chemical modification of rapeseed oil with sulfur compounds. The results indicate that the friction and wear of the magnesium alloy-steel tribomates could be effectively reduced by formulating SRO into rapeseed oil lubricant. The friction coefficients and the wear volumes of magnesium alloy decrease with increasing contents of SRO. The surface lubricated with SRO-doped rapeseed oil was characterized by less wear as compared with that lubricated with neat rapeseed oil. The enhanced anti-wear and friction-reducing abilities of rapeseed oil by SRO in the lubrication of magnesium alloy against steel were ascribed to the formation of a composite boundary lubrication film due to the strong adsorption of SRO and rapeseed oil onto the lubricated surfaces and their tribochemical reactions with magnesium alloy.
文摘Neodymium dialkylthiophosphate (NdDDP) with alkyls of isopropyl and isooctyl were synthesized by exchanged reaction respectively. The structures of the two NdDDPs were determined using IR and XRD. Properties of anti-wear and friction-reducing of the two additives were investigated with four ball experiment and the commercial anti-wear additive ZDDP was selected as control. The elemental analysis of the wear scars after 10 s friction at low stress were investigated by EDXA (Energy Dispersion Analysis of X-ray). Primary results showed that the NdDDPs possess better lubrication ability than ZDDP. This might mainly be contributed to the formation of a boundary film containing Nd2O3, FeS and sulphate, phosphate, organo-sulfide, etc., and a neodymium-rich diffused layer which changes the crystal structure of the surface of friction materials.
基金financially supported by the National Natural Science Foundation of China (Project No. 51375491)the Natural Science Foundation of Chongqing(Project No. CSTC, 2014JCYJAA50021)the Youth Fund of Logistical Engineering University (No. YQ16-420801)
文摘Considering electromagnetic effect when investigating tribological properties of rapeseed oil is benefical not only to the improvement of green lubrication, but also to the development of tribology theories and practices. In the present paper, the tribological properties of rapeseed oil under different intensity of electromagnetic field and normal loads were evaluated on a modified tribo-tester. The results indicated that the electromagnetic field could improve the anti-wear and friction-reducing property of the rapeseed oil. Furthermore, the influencing mechanisms were discussed from the perspective of electromagnetism according to the analytical results of SEM, EDS and XPS techniques.
文摘Cu-doped muscovite(Mu) composite particles, abbreviated as Mu/Cu, were prepared via liquid phase reduction method. The morphologies, phase composition and elementary distribution of the as-prepared Mu/Cu and raw muscovite particles were characterized by means of scalmmg electron microscope(SEM), X-ray diffraction(XRD) and energy dispersive spectrometry(EDS). The tirbological properties of Mu/Cu and Mu as lubricant additives in lithium grease were evaluated on a block-ring tribomachine. The roughness, 2D and 3D morphologies and elementary distribution of block worn surface were analyzed to explore the tribogical mechanism. The results show that muscovite are evenly coated by the cubic Cu nanoparticles in composite particles. Both Mu/Cu and Mu can effectively improve the tirbological properties of lithium grease and Mu/Cu exhibits better tribological performance than Mu. The friction coefficient of Mu/Cu is decreased by 69.2% as compared to that of lithium grease. The layer structure of muscovite is synergistic with Cu nanoparticles in contribution to the formation of lubricant film mainly consisting of O, Si, Fe, Cu as well as Al elements on the block worn surface thereby further reducing the friction and wear.