| On the base of reviewing many kinds of preparation method of nano metal powder materials, at the same time, after doing a lot to contrast the capability among the preparation methods of ultrasonic electrolysis, ultrasonic immersion electrolysis and electrolysis emulsification, we think that the preparation method of electrolysis emulsification have many excellent characteristics such as the controlled particle, the better dispersancy, the simple equipments, the cheap cost of production, pollution free, the notable output rate, etc. Some particle-controlled ultrafine metal powder materials such as Cu, Ag, Zn were prepared by electrolysis emulsification method. Take the preparation of copper powder for instance, the inner mechanism was expatiating in this thesis.On the contrast of the capability among the preparation methods of ultrasonic electrolysis, ultrasonic immersion electrolysis and electrolysis emulsification, the importance of emulsified liquid which can envelop the copper powder was found in the course of preparing copper powder. The preparation of emulsified liquid and the choice principle of emulsifying agent were analyzed deeply in my thesis. According to the experimental result, the pomade and the emulsifying agentbelonging to alkylbenzene sulfonate were composed the formula of the emulsified liquid.The technique process of the ultrofine copper powder which use electrolysis emulsification method and the preparing equipment were explained at length in my thesis. Base on the single-factor experiments, the rule which the current density, PH and the consistence of CuSO4 affect the average particle diameter and the output rate of n-Cu and μ-Cu powder was found by us. The result is as follows, with the increasing of the current density and PH , the particle diameter was minished; the increase of the current density and the consistence of CuSO4 will lead to the elevation of the output rate of ultrofine copper powder, the increase of PH is the other way about.On the base of single-factor experiment, the experimental data were analyzed using the F proof-test method, the order which based upon an assessment of the degree of effect on the output rate and particle diameter of copper powder was obtained. We think that the PH has obvious effect on the particle diameter; on the other hand, the current density affects the output rate evidently. On this basis we can increase the output rate of ultrofine copper powder by adjusting the technology parameter on the premise that the particle diameter of powder was promised.The mathematic expression between technology factors and the output rate of powder have been obtained. The single-factor regression analysis of experiment data show the quantitative relation which will become the direction of subsequent experiment between technology factors and the output rate of copper powder by the soft ware of SPSS11.0 for Windows.The overpotential was considered as the dynamics factor of the preparation of copper powder. Both of technology factors such as current density, PH affect the particle diameter via affecting the overpotential of cathode. We have studied the crystallization process and the critical state of nucleation and growth. And the relation between the overpotential of cathode and the critical state was known by further study, as a result, the increase of the overpotential of cathode is favorable to the thinner of copper powder. After studying deeply the effect of current density andPH on the overpotential of cathode, we have obtained the effect rule between technology factors and particle diameter of ultrafine copper powder.Current density is the direct factor which affects the output rate of copper powder which can be proved by faraday's law. On the other hand, the effect of the electrode potential of cathode on the activation energy which formed in the course of reaction is studied, which explains the effect of PH and the consistence of CuSO4 on the output rate of ultrafine copper powder.
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