热压烧结制备La混杂纳米复合AgSnO2电接触合金

La-Doped Nanocomposite Ag-SnO2 Contacts Prepared by Hot Pressing

摘要:

利用化学共沉淀和热压烧结等方法制备出纳米复合Ag-SnO2和La掺杂Ag-SnO2触头合金，对合金触头进行物理性能测试、真空耐电压和电弧烧蚀实验，并利用冷场发射扫描电镜(FESEM)对电性能实验前后组织进行分析。结果发现：纳米复合AgSnO2电接触合金保持了制粉时纳米SnO2颗粒的形貌和粒度，尤其是含La掺杂的电接触材料，其氧化物粒度更细，分布更均匀。随氧化物粒度的减小，电接触材料的硬度和电阻率增加、耐电压强度降低、耐电弧烧蚀速率减小

Abstract:

The nanocomposite Ag-SnO2 and La-doped Ag-SnO2 electrical contact alloys are prepared by chemical co-precipitation method and hot pressing and sintering technique. The main physics performances were measured in this paper. The breakdown field strength of contacts alloys were investigated in vacuum and the microstructures are observed by field emission scanning electron microscopy. The results show that the nanosized SnO2 of the same morphology and grain size as the prepared powders，disperses evenly in the Ag based. Especially for the La-doped nanocomposite Ag-SnO2 contact alloys, the oxide grain size is less, and disperses more evenly. With the oxide grain size decreasing, the hardness and electrical resistivity increase, and the breakdown field strength and the arc erosion rate decrease.