Effects of Diesel Fuel Nano-Additives on Friction and Wear Properties of Precision Coupled Parts of a Diesel Engine Fuel Injection System

Due to the unique redox characteristic of CeO2, the addition of CeO2 in diesel fuel reduces diesel engine emissions; however, its influence on the friction and wear performance of fuel injection systems is not clear. In this work, CeO2 was synthesized and modified. CeO2–diesel fuel blends with different concentrations were prepared. The dispersion stability of the CeO2 and modified CeO2 in diesel fuel blends was measured. The results indicated that the dispersion stability of the modified CeO2 in diesel fuel was improved. The effects of adding modified CeO2 to diesel fuel on the friction and wear properties of the fuel injector body were studied. Test results showed that the friction coefficients of all of the diesel fuel blends were the same after running in at normal temperature. At high temperature, the friction coefficients of diesel fuel blends with 10, 25, 50, and 100 ppm CeO2 added were reduced by 14.03, 25.27, 24.31, and 10.58%, respectively, compared with that of neat diesel fuel. Both the width and maximum depth of the wear scar were reduced to different degrees, and the diesel fuel blend dosed with 25 ppm CeO2 had the best antiwear ability at normal temperature and high temperature.HIGHLIGHTSThe morphology of modified CeO2 was spherical and relatively uniform.The dispersion stability of modified CeO2 in diesel fuel was improved.The addition of CeO2 in diesel fuel improved the friction and wear performance.With an increase in CeO2, the range of improvement first increased and then decreased.The diesel fuel blend with 25 ppm CeO2 added showed the best friction and wear performance.