| Superfine powder technology mainly includes the preparation, the properties researching and the study on the application of superfine powder. The superfine powder preparing technology is considered to research the new principle of the preparation, the method of preparation and concerning equipments. The aim is to prepare powders of much more fine, more narrow distribution and more uniform. What the research of application is to apply the superfine powder to national economy and solve all kinds of the problems following the application. But with the rapid development of the materials science, the research on the properties of superfine powder will become the main task of the superfine powder technology in the future. The aim of the research on the superfine powder properties is to prepare new, functional properties and complex superfine powder, by designing or compounding modification on superfine particles.In the composite methods of superfine powder, mechano-chemistry is more and more popular and received by majority, because this method has a splendid prospect application. It's a new sort of cross subject. What's the method of the mechano-chemistry is mainly find out the basic principle, rule and application of the physical-chemical reaction occurring to the superfine powder, in the effect of the mechanical force in all kinds of conditions. The appearing of mechano-chemistry method displays a new wide field for the processing of new materials. On the basis of the mechano-chemistry principles, three kinds of functional composite particles were prepared by different mechanical force, according to the actual requirement of commerce areas.1. The moderate supersonic carbon added to the mold flux for ultra-low carbon steel is used to stay the melting speed as skeleton. Then the mold flux coils have the good adiabatic, insulation and even flow property. At the same time it cause the carbon increase in the steel slabs and the operation of the ultra-low carbon is affected at last. The strong shear cut and grinding force of HLGB horizontal stirring grinding machine is used to the surface of the moderate supersonic carbon and the fusion particles of the CaO & SiO2 in this paper. The result of XPS indicated that the Si-C bond is detected on the surface of the particles. The high melting point superfine SiC and CaCO3 areproduced on the surface of CaO & SiO2, and composite particles are formed. As the melt speed of SiC in steel water is very slow and SiC has the function of restrain the melting of free carbon in steel water, so the contain of carbon in steel is decreased.On the other hand, under the force of mechanical, the carbon and CaO & SiO2 superfine powder are obtained; the specific surface area of these particles is increased. The TEM photos indicated that, the carbon particles are composites on the surface of the melting superfine particles uniformly. In doing so, the utilization rate of carbon is increased and the melting speed of protection slag is decreased. The application result indicated that: using superfine composite particles, only 0.3% of carbon is needed, while carbon in traditional particles would up to 2%. Hence, the adding of superfine composite powder can avoid the increasing of carbon in steel slag.2. When graphite is applied in the areas of war, such as the disappearing material, the Graphite Bomb and so on, superfine powder is needed and carbon in the form of steadily aerosol is required. According to the properties of the crystal carbon, the opposing pulverizer was employed to prepare the superfine carbon in this paper. Based on the principle of mechano-chemistry, the strong shock and crashing mechanical force produced by LS-250 pulverizer can act to the surface of superfine carbon and white carbon particles during the process. The result of the experiment indicated that distortion and amorphism change occur to the surface crystal lattice of carbon particles, and the phenomena are prick up as the action time of mechano-chemical force. In this processing, the superfine particles...
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