Controllable Preparation of SnO2 Microspherical and its Application in Electrical Contact Material

Abstract:

SnO₂ microspherical (SnO_2(s)) were successfully prepared by hydrothermal method at 180℃ for 25 hours,using SnCl₄.5H₂O and NaOH as raw materials. And Ag- SnO_2(s) electrical contacts material were obtained by high-balling and sintering processes; Effects of surfactants, hydrothermal time and pH on the morphology of SnO₂ microspheres were studied；The morphology, structure and other physical properties of Ag-SnO_2(s) electrical contacts material were characterized by Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), Transmission Electron Microscopy (TEM), Vickers Hardness Tester and Conductivity Meter. The results show that monodispersed SnO2 microspheres with a diameter of 1 ~ 4 μm were obtained using CTAB as the template at pH=13 with hydrothermal time for 25h. The electrical resistivity and density of Ag-SnO_2(s) electrical contacts material are respectively 3.18 μΩ.cm and 71.5 g.cm_-3, which is better than that of traditional Ag-SnO_2(p) electrical contacts material with nano SnO₂ particulates as the second reinforecement.