In situ formation and doping of Ag/SnO2 electrical contact materials

The Ag/SnO 2 electrical contact materials with different doping concentration of Zr and Fe were successfully fabricated through self-assembly precipitation and powder metallurgy method. The microstructures of Ag-SnO 2 composite powders and the prepared Ag/SnO 2 contact materials were investigated by a Scanning Electron Microscopy (SEM) coupled with EDS and EBSD systems. The results showed that the SnO 2 nanoparticles with typical geometric shapes were formed and distributed in Ag matrix. The electrical conductivity of the Ag/SnO 2 materials was significantly increased by 16 percent with the doping of 3 wt% ZrO 2 in SnO 2 . The surface morphology of the Ag/SnO 2 materials after arc erosion was further characterized. The formation of the Sn(Zr)O 2 and Sn(Fe)O 2 solid solution in Ag/SnO 2 significantly improved the arc dispersion and arc erosion resistance. This work can offer a novel approach to design Ag/SnO 2 contact materials for good electrical performances.