| Due to its special physical and chemical characteristics, nanometer-level solid lubricant has received more and more attention and has developed quickly. Currently the main interest of researchers is focused on producing nanon particles by aggregation method, however, these particles are certainly difficult to be produced in an industrial scale because of complicated technology, careful operations and high cost required. Another widely used method in industry, the machine-grinding method has the features of simple technology, high production efficiency and batch production, but the particles from this method are difficult to achieve nanometer level, and the smallest ones can only go to micron level. So far there is no report about nanometer-level particles produced by this method. It is possible that, when being pulverized by machine-grinding method, the particles will reaggregate because of the increase of surface energy. And the aggregation will accelerate during the pulverization. When the aggregation speed equals to the pulverization speed, the particles are in the dynamic balance between aggregation and pulverization, and the size of it will not reduce any more. So by means of combining both enhancing pulverization so as to increasing the pulverization speed and intensifying dispersion by employing "shell" structure to the effect of decreasing the aggregation speed, the particles will be pulverized smaller, even to nanometer level. In this research, combiningpulverization theory and colloidal theory, we designed and manufactured a nanometer ball mill unitizing strengthening pulverization to accelerate the pulverization and strengthening dispersion to decelerate the aggregation. And taking it as a simulation device of production, we prepared three types of nanon solid lubricant. Their friction mechanism was analyzed and they were compared with the commercial nanon-level graphite fluoride on the tribological characteristics.In this dissertation, three solid lubricants, MoS2, PTFE and French chalk commonly used in industry, were selected as the main raw materials and samples were prepared through a series of preparation experiments with nanon ball-mill designed and manufactured by the author. By SEM and TEM the shape and particle diameter of raw materials and prepared samples were analyzed and processing technology parameters of nanon ball-mill were studied with the result of the optimal technology parameters as following: rotational speed 2800 r/min; time of grinding 12h; diameter of steel ball 2mm; volume percentage of oil 40%; filling rate of ball 3 5%.On the basis of these optimal technology parameters of nanon ball-mill, the effects of viscosity of lubricant oil, quantity of raw material added, and various surfactants used in the preparation of nanon-level solid lubricants were investigated. It is found that low oil viscosity and less quantity of raw material matched with the optimal dispersant to any of the above three solid lubricants are beneficial to preparing nanometer particles, with the help ofdispersing agent T154 compounded with oil barium sulfonate,晄nanon-level MoS2 with average diameter of 40nm and minimum one of 1 Onm can be processed and with the help of dispersing agent T154 compounded with chlorinated paraffin wax, nanon-level PFTE with average diameter of 20nm and minimum one of 10nm can be processed. And when dispersing agent T154 is compounded with dispersing agent T306, nanon-level French chalk with an average diameter of 40nm and a minimum one of 10nm is produced. Moreover all of them have even particle-diameter and good dispersivity. In addition we specially pre-process PTFE by Co60 irradiation before its smashing and grinding because flexible PTFE is difficult to be ground. It was shown that any PTFE non-radiated or inadequately radiated cannot be manufactured into nanon-level particles, and PFTE with radiation of 200K can be made into about 20nm-diameter particles. The reason of this phenomenon is that their molecule skeletons have been unbent although there is n...
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