AgSnO2电接触材料具有优良的抗电弧侵蚀性和抗熔焊性,在交直流接触器、功率继电器和低压断路器等领域已经部分或全部取代了AgCdO材料。内氧化法是制造AgSnO2电接触材料工艺最成熟、应用最广泛的一种方法。本文计算了Ag-Sn合金的内氧化热力学条件参数,论述了内氧化过程中SnO2颗粒的形核、长大和粗化过程,并采用合金粉末成形-内氧化-热挤压新工艺制备了SnO2颗粒细小弥散、性能优越的AgSnO2电接触材料。
AgSnO2 electrical contact materials have excellent electrical arc resistance and good welding resistance, and have been partially or fully replaced AgCdO materials in the field of AC and DC contactors, power relays, and low-voltage circuit breakers and so forth. The internal oxidation is a most mature and widely used method for manufacturing AgSnO2 electrical contact materials. In this study, we calculated the internal oxidation thermodynamics of Ag-Sn alloy, and investigated the mechanisms of the nucleation, growth and coarsening of SnO2 particles during internal oxidation. The AgSnO2 electrical contact materials with small and dispersed SnO2 particles and superior performances were obtained by a new technology: a combination of alloy powder forming, internal oxidation, and hot extrusion process.