Study Of Electroless Plating Of Nano-doping AgSnO₂ Electrical Contact Materials

Electrical contacts are the contact components of the electrical switches and instruments. Its main burden is the disconnection of the circuit, which strongly affects the performance of the reliable operation of electrical switches and life. Extremely complex phenomenon will occur during the process of opening and closing in the circuit, and many factors will affect it. The ideal electrical contact materials must have good physical properties, electrical contact performance and processing performance. Current research shows that, AgSnO₂ contact material is an ideal subtitute of AgCdO. But there are also some weaknesses in it, for example, large contact resistance, high temperature rise and poor processability.In this paper, we prepared doped Bi-SnO₂ nano powder by using the Sol-Gel method, and analyzed the SnO₂ crystal transition temperature through the DTA-TG and X-ray diffraction analysis. According to microscopic analysis, it was shown that the distribution of SnO₂ powder was homogeneous with their particle sizes about 10 nm. Then we researched the electroless plating process of nano-particles SnO₂ and investigated the influence of temperature, reductant and concentration to the electroless plating process. It was found that best reductant is glucose, the best temperature is 60℃and the best concentration is 0.6 Mol/L.Then, through the X-ray diffraction analysis(XRD), scanning electron microscope (SEM) and energy spectrum analysis, the relationship between the component and microstructure of the electroless plating powder was investigated, and the formation mechanism of metal plating was clarified from the perspective of a redox.We prepared the nanometer doping AgSnO₂ contacts by powder metallurgic process and test their density, rigidity, strength of compress. Then we compare the performance of AgSnO₂ contacts that we prepared to GB. The result indicated that the performance of our contacts is much better than GB.