Preparation and tribological properties of stearic acid modified LaPO_4 and Ce/LaPO_4 nanoparticles

Stearic acid modified LaPO4 and Ce/LaPO4 nanoparticles were synthesized by precipitation method.The morphology and structure of nanoparticles were investigated by infrared spectroscopy(IR),X-ray diffraction(XRD) and transmission electron microscopy(TEM).The dispersibility and stability of nanoparticles additives in solvent were studied.The tribological properties of modified LaPO4 and Ce/LaPO4 nanoparticles were investigated by four-ball machine.Results showed that stearic acid modified LaPO4 and Ce/LaPO4 nanoparticles average size 10nm,and the modified nanoparticles exhibit good dispersion in organic solvents.The wear resistance and load-carrying capacity of the liquid paraffin with nanoparticles added were improved in comparison with the liquid paraffin.When the stearic acid modified LaPO4 and Ce/LaPO4 nanoparticles were added into liquid paraffin,the PB value of the oil sample could be increased by 0.75 and 1.1 time,the wear scar diameter of steel ball could be reduced by 41% and 49%.