CeF3. CaF2, (CF)n, SbF3, and CeO2 were selected as the high temperature solid additives in a lithium grease, and their friction, wear, and extreme pressure properties were evaluated on an Optimol-SRV wear tester. The ...CeF3. CaF2, (CF)n, SbF3, and CeO2 were selected as the high temperature solid additives in a lithium grease, and their friction, wear, and extreme pressure properties were evaluated on an Optimol-SRV wear tester. The effect of additive on the fiber structure of soap was studied by means of the transmission electron microscopy(TEM). The corrosive property of grease containing additive was evaluated by copper strip corrosion test. Thermal decomposition behaviors of the additives were studied by thermogravimetry(TG) tester. The adhesive strength of rubbing surface film was measured by automatic scratch tester and the wear surface was detected by means of X-ray photoelectron spectroscopy (XPS). The test results showed that the grease containing CeF3 has good anti-wear, anti-friction, and EP performances, and has high adhesive strength of rubbing surface film.The greases containing CaF2 or (CF)n are good in antiwear and anti-friction properties, but poor in extreme pressure function. The tribological properties of the grease containing SbF3 are decreased.And the addition of CeO2 in grease was useless. Finally the mechanism of fluoride additive was proposed in this paper.展开更多
The oil-soluble cadmium dipropyldithiophosphate additive was synthesized. A four-ball tester was used to evaluate the tribological performance of the additive in a mineral oil under different loads and lubricant greas...The oil-soluble cadmium dipropyldithiophosphate additive was synthesized. A four-ball tester was used to evaluate the tribological performance of the additive in a mineral oil under different loads and lubricant grease synthesized compared with some commercial additives. The results show that it exhibits excellent antiwear and load-carrying capacities and is better than other additives. The surface analytical tools such as scanning electron microscope (SEM) with energy dispersive X-ray (EDX), X-ray photoelectron spectrometer (XPS) were used to investigate the topography, the compositions, and chemical states of some typical elements on the rubbing surface of worn scar.Smooth and light topography of worn scar further confirms that the additive shows good antiwear capacities. The results of EDX and XPS analyses indicate that tribochemical mixed protective films consisting of atomic cadmium, sulphides, sulphates and phosphates are formed on the rubbing surface, which contribute to improving the tribological properties of lubricant and grease. Particularly, the soft cadmium film formed plays an important role in improving antiwear properties of oils. Finally, antiwear mechanism of the additive and formation scheme of atomic cadmium was proposed.展开更多
文摘CeF3. CaF2, (CF)n, SbF3, and CeO2 were selected as the high temperature solid additives in a lithium grease, and their friction, wear, and extreme pressure properties were evaluated on an Optimol-SRV wear tester. The effect of additive on the fiber structure of soap was studied by means of the transmission electron microscopy(TEM). The corrosive property of grease containing additive was evaluated by copper strip corrosion test. Thermal decomposition behaviors of the additives were studied by thermogravimetry(TG) tester. The adhesive strength of rubbing surface film was measured by automatic scratch tester and the wear surface was detected by means of X-ray photoelectron spectroscopy (XPS). The test results showed that the grease containing CeF3 has good anti-wear, anti-friction, and EP performances, and has high adhesive strength of rubbing surface film.The greases containing CaF2 or (CF)n are good in antiwear and anti-friction properties, but poor in extreme pressure function. The tribological properties of the grease containing SbF3 are decreased.And the addition of CeO2 in grease was useless. Finally the mechanism of fluoride additive was proposed in this paper.
文摘The oil-soluble cadmium dipropyldithiophosphate additive was synthesized. A four-ball tester was used to evaluate the tribological performance of the additive in a mineral oil under different loads and lubricant grease synthesized compared with some commercial additives. The results show that it exhibits excellent antiwear and load-carrying capacities and is better than other additives. The surface analytical tools such as scanning electron microscope (SEM) with energy dispersive X-ray (EDX), X-ray photoelectron spectrometer (XPS) were used to investigate the topography, the compositions, and chemical states of some typical elements on the rubbing surface of worn scar.Smooth and light topography of worn scar further confirms that the additive shows good antiwear capacities. The results of EDX and XPS analyses indicate that tribochemical mixed protective films consisting of atomic cadmium, sulphides, sulphates and phosphates are formed on the rubbing surface, which contribute to improving the tribological properties of lubricant and grease. Particularly, the soft cadmium film formed plays an important role in improving antiwear properties of oils. Finally, antiwear mechanism of the additive and formation scheme of atomic cadmium was proposed.
