Tribological performance of nanometer samarium borate
(1. Department of Mechanical Engineering,
Chongqing Institute of Technology, Chongqing 400050, P.R.China；
2. Department of Petroleum Applied Engineering，
Logistic Engineering College, Chongqing 400016, P.R.China)
Chongqing Institute of Technology, Chongqing 400050, P.R.China；
2. Department of Petroleum Applied Engineering，
Logistic Engineering College, Chongqing 400016, P.R.China)
Abstract: Nanometer crystal samarium borate with a particle size of 20～40 nm was prepared using replacing solvent drying technique. The wear resistance and loadcarrying capacity of 500SN base oil could be improved and the friction coefficient could be decreased by the addition of nanometer samarium borate. But the dosage of samarium borate nanoparticles had to be controlled at a relatively low level, a higher concentration of nanoparticles was not of beneficial to the tribological performance of the oil. The optimal dosage of nanometer samarium borate is 1.0%. Tribochemical reactions took place in the tribological process, which resulted in the formation of deposition products including diboron trioxide and disamarium trioxide. Fe2B and FeB were also found on the wear scar. The improvement of tribological properties of the oil comes from the formation of deposition layer and permeating layer.
Key words: nanometer particle； samarium borate； tribology； action mechanism