| In this paper, we successfully produced a Nano-Ag-SnO2 contact material by highenergy ball milling. Through researching conditions of ball milling technics, such asmediums of ball milling, dispersants, the ratio between the weight of materials andballs, the time of milling, and so on, we have gain the best optimal parameters ofproducing Nano-Ag-SnO2 electrical contact material by high energy ball milling, andstudied the influences and operational principles of performances of electrical contactmaterials by the different quantities of La2O3 and the different thulium oxides.The researching results indicate that the performances of contact materials,suchas electrical conductivity, rate of heat transmits, fluidity of liquid are remarkablyimproved by management of high temperature diffused adulterating SnO2 with TiO2,which also has reduced the electrical arc erosive probability of Ag-SnO2 electricalcontact materials, the physical properties of Nano-Ag-SnO2 contact materials, such asdensity, hardness, electrical conductivity are remarkably improved by high energy ballmilling. The materials that produced by this technology have higher hardness, finerelectrical conductivity, finer and more dispersive microstructure, which has afavorable foreground of application.The SEM pictures of microcosmic structure and analysis of EDS indicate thatboth SnO2 and thulium oxide distribute equably dispersively in the Ag-base, andLa2O3 mainly distribute in the crystal boundary which prevent the Ag-SnO2 crystalparticles from growing up, and it obviously has functions of making crystal particlesthined and dispersion strengthened so as to improve the mechanical and physicalproperties. But because of this condition, it increases the probability of electronscattering at the same time, thereby the conductibility of contact material is reduced.But it can improve the mechanical property and reduce the little conductibility ofcontact material with little content of thulium.
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