Research On The Tribology Performanceof Bn Nano-particles As Lubricant Additives

This article describes the synthesis and applications of nano-materials, moreover, the surface modification of nano-particles. Spherical h-BN nano-particles were successfully synthesized and lots of surface modification experiments for these nano- particles were made. The method of spherical BN synthesis in this experiment is: first we need synthesize the mixtures 3-hydroxy acid ester and boric acid. Then the mixtures were carried by nitrogen or inert gas into the annealing furnace which excessive amount of ammonia. After reaction at high temperature 1350℃, spherical h-BN nano-particles were obtained.As the h-BN nano-particles reunion easily, it is difficultly that dispersion stable which they added into lubricating oil. So surface modification need to be done for this problem. In this article, we selected EDTA-2Na, KH-570, PVP and sterol chloride as surface modification agents. They base on the principle of physical modification and chemical modification. This experiment process contains heating, stirring, ultrasound and other methods, for h-BN nano-particles surface modification. Then the BN nano-particles modified for doing experiment about hydrophilic and lipophilic. Seven days later, the results indication: The h-BN nano-particles by PVP modified that hydrophilic is well, so as the stearoyl chloride modified in pro-oil.BN nano-particles modified by stearoyl chloride, whose surface tension reducing and surface wettability improving. So they were dispersed into base oil stably and equably. The lubricant oil added this additive has done friction and wear experiments on four-ball friction equipment. After experiments, it proves that this additive reduces the friction coefficient of base oil and improves the tribological properties for showing a good anti-wear antifriction effect.