Preparation Of Oil-soluble Nano Copper Particles In Microemulsion And Its Tribological Application

The nano copper particles, as a new lubrication additive material, have been used widely in tribology for its excellent antiwear properties, thermal stability and corrosion resistance as compared with conventional additive. As a result, more and more people take an active in doing research on the preparation and application of nano copper. In this thesis, the oil-soluble nano copper particles were prepared by chemical reduction in the microemulsion base on collochemistry, surface chemistry and nanometer material technology. And the tribological properties of the nanophase copper in lubricating oil were investigated also by tribology testing. The mechanism of antifriction of the copper nanoparticles as lubrication additive was presented by the author: The copper nanoparticles were dispersed in the base oil by means of coating with the surface-activators instead of bare copper particles, and the "elastic microballoon sphere cells" were composed with copper nanoparticles as the center of sphere and surface-activators as the surface layer. The main research production comprised three parts as below:1. The nano copper particles which sized about 20nm with a small partition of conglome-ration were obtained by chemical reduction in the microemulsion. The proper technology condition of preparation was studied in terms of activator, reaction sequence, solution concentration, scatter operation and temperature. The nanophase copper lubricant additive I6 was prepared eventually.2. The tribological properties of the nano copper additive I6 were studied by means of friction test, and the results indicated that I6 additive performed excellent wear resistance effect. It shows that I6 makes the base oil HL68 and HL46 have an increase of 34.95 percent and 23.47 percent in terms of P_B respectively, and have a decrease of 78.3 percent and 53.8 percent in terms of friction coefficient. I6 can make the test button have a relatively negative wear extent on high velocity and low-load condition.3. The mechanism of antifriction of the copper nanoparticles was discussed in this article:â‘ The copper nanoparticles were dispersed in the base oil by means of coating with the surface-activators instead of bare copper particles, and the "elastic microballoon sphere cells" were composed with copper nanoparticles as the center of sphere and surface-activators as the surface layer. The perfect antifriction and tribology characters were probably attributed to the elastic microballoon sphere cells which was prone to slip on high velocity and low-load condition as a result of the specific structure, while on low velocity and over-load condition, the load bearing and separate action of the copper nano- particles were main factors to the antiwear property.â‘¡The nano copper particles may be melted for the hyperthermia of the rubbing effect and adhered on the friction surface. It was possible that theadherence action of the nanoparticles made the resistance to abrasion.