Facile synthesis of silver-tin oxide electrical contact materials by in-situ decomposition of a uniform mixture precursor

Abstract

A uniform mixture precursor containing Ag2O and Ag2SnO3 was synthesized via a facile ion exchange reaction method. The influence of pH value on composition and precipitation rate of the precursor was investigated systematically. The Ag-SnO2 composite powder was obtained by decomposition of the precursor at 600°C, and uniform mixing of elements was inherited from the precursor and fresh and intimate Ag-SnO2 interfaces were created. The Ag-SnO2 electrical contact material was prepared using this composite powder by hot-pressing method. It was found that nano-sized SnO2 particles (about 20.6 nm) are homogeneously dispersed in the Ag-matrix. The as-prepared Ag-SnO2 electrical contact material shows excellent performances, such as high hardness (154 MPa), high density (9.90 g/cm3) and good electrical conductivity (72.24 %IACS).