Abstract: Carbon nano onions (CNOs) were prepared by chemical vapor deposition (CVD).The outer layer was graphite layer, which contained Fe-Ni catalyst particles, and the shape was similar to spherical and played the role of "micro-bearing" in mechanical lubrication.The friction performance of the lubricant additive was investigated by rotating oxygen bomb method, four-ball friction tester and lubricating oil anti-wear tester.The results show that carbon nano onions have good anti-wear performance.When the mass fraction of CNOs is 0.05;, the abrasion resistance of lubricating oil is improved obviously.At this time, the extreme pressure value is increased by 64;, the diameter of grinding spot is reduced by 78;, and the oxidation stability is better.

Key words: Carbon nano onions (CNOs) were prepared by chemical vapor deposition (CVD).The outer layer was graphite layer, which contained Fe-Ni catalyst particles, and the shape was similar to spherical and played the role of "micro-bearing" in mechanical lubrication.The friction performance of the lubricant additive was investigated by rotating oxygen bomb method, four-ball friction tester and lubricating oil anti-wear tester.The results show that carbon nano onions have good anti-wear performance.When the mass fraction of CNOs is 0.05;, the abrasion resistance of lubricating oil is improved obviously.At this time, the extreme pressure value is increased by 64;, the diameter of grinding spot is reduced by 78;, and the oxidation stability is better.