(1. 中南大学 材料科学与工程学院，长沙410083；
2. 中南大学 有色材料科学与工程教育部重点实验室，长沙410083)
摘 要: Ag/SnO2电接触材料具有良好的耐电弧侵蚀和抗材料转移性能，广泛应用于低压断路器和继电器中。 然而，其制备初期组织和物理性能对产品铆钉的电性能有着最直接和极为重要的影响。采用X射线衍射分析仪(XRD)、场发射扫描电镜(SEM)和电子探针显微分析仪(EPMA)等手段，分析合金元素Sb、La和In对Ag/SnO2材料制备初期组织演变和物理性能的影响。结果表明：添加Sb、La 和In的Ag/SnO2烧结坯中除了含Ag和SnO2相外，还分别含有AgSbO3、La2Sn2O7和2In2O3？3SnO2相。添加Sb的Ag/SnO2烧结坯中氧化物主要在粉末边界上呈网络状分布；添加La的Ag/SnO2烧结坯中氧化物颗粒细小，且均匀弥散分布；添加In的Ag/SnO2烧结坯中氧化物呈块状分布，且存在纯银层。添加In的Ag/SnO2材料的电导率和硬度最高，添加Sb的Ag/SnO2材料的相对密度最大。
关键字: Ag/SnO2材料；合金元素；组织演变；物理性能
（1. School of Materials Science and Engineering, Central South University, Changsha 410083, China;
2. Key Laboratory of Nonferrous Materials Science and Engineering, Ministry of Education, Central South University, Changsha 410083, China）
Abstract:Ag/SnO2 electrical contact material has excellent arc erosion resistance and material transfer resistance, which is widely used in low-voltage circuit breakers and relays. However, the microstructure and physical properties at the initial stage of preparation have the most direct and important influence on the electrical properties of the rivets. In this paper, the influence of alloying element Sb, La and In on the microstructure evolution and the physical properties of Ag/SnO2 materials at the early stage of reaction synthesis were studied by X-ray diffractometer (XRD), scanning electron microscope (SEM) and electron probe X-ray micro-analyzer (EPMA). The results show that, besides Ag and SnO2 phases, AgSbO3 phase exists in Ag/SnO2 sintered compact with Sb adding, La2Sn2O7 phase exists in Ag/SnO2 sintered compact with La adding, and 2In2O3？3SnO2 phase exists in Ag/SnO2 sintered compact with In adding. The oxides in the Ag/SnO2 sintered compact with Sb mainly distribute on the alloy powders surface and form network microstructure. The oxide particles in the Ag/SnO2 sintered compact with La are fine and dispersed uniformly. The oxides in Ag/SnO2 sintered compact with In are distributed in blocks, and there is a pure silver layer. The conductivity and hardness of the Ag/SnO2 material with In are the highest, the relative density of the Ag/SnO2 material with Sb is the largest.
Key words: Ag/SnO2 materials; alloying element; microstructure evolution; physical properties
