The design of surface modification of amorphous ZrO2 nanoparticles as a lubricant additive

ZrO2 is a kind of inorganic material with high hardness, high tenacity, antiwear, corrosion, and resistance, therefore it is regarded as an ideal nanolubricant material. But untreated ZrO2 nanoparticles are reunited in the lubricant medium instead of monodisperse because the consistency is poor between the material surface and lubricant, which restricts its application as a nanolubricant additive. Through theoretical analysis, this paper designed that the surface of ZrO2 nanoparticles was modified with silicon coupling agent, and it was changed to lipophilic surface, so it was possible to be a monodisperse system in the lubricant. The modified spherical nanoparticles of ZrO2 were dispersed in the lubricant and they could play a molecular bearing part in lubricating media. When the friction surface reached a certain load and temperature, once the metal surface produces the deficiency, physical adsorption and chemisorption on the metal surface would be produced because of high nano-ZrO2 particle activity, and even the N atom in the particle surface silane tends to be absorbed to the metal surface to form chelate compound, and make ZrO2 particles enrich to defective locations of the metal surface. Then, a self-repairing lubricated membrane in the friction surfaces was set up, and it can play the function in the antifriction, antiwear, and surface dynamic self-repair.