中文摘要：

应用高速数字摄像机和扫描电镜对纳米复合Ag-SnO2，Fe掺杂的纳米复合Ag-SnO2及商用Ag—SnO2-In2O3电接触合金的电弧演化过程和阴极斑点进行了比较研究。结果显示：空气中电弧的演化过程可以分为起弧、稳定燃烧和衰减3个阶段。Fe掺杂后，纳米复合电接触合金电弧演化过程的形弧时间是商用合金的2倍；对触点表面烧蚀起主要作用的稳定燃烧时间短；电弧弧根对应的阴极斑点数量多、跳动迅速、运动区域大；电弧弧根在阴极表面停留的时间短，热流输入少，使其燃弧后阴极斑点分散，烧蚀轻微，具有较好的耐电弧侵蚀性能。

英文摘要：

The arc evolution and cathode spots of nanocomposite Ag-SnO2, Fe-doped nanocomposite Ag-SnO2 and commercial Ag-SnO2-In2O3 contact alloys were researched by high-speed camera and scanning electron microscopy （SEM）. Experimental results show that the evolution of arc discharge in air can be divided into three stages： arc forming, steady burning of arc and attenuation. Compared with commercial Ag-SnO2-In2O3, aRer Fe doping, nanocomposite Ag-SnO2 contact has double time of arc forming and shorter time of steady burning. It also has more cathode spots corresponding arc roots which jump fast and have a larger motion region on the contact surfaces, as a result of the time of arc roots stay on the contact surfaces is shorter, and therefore the heat stream input cathode spots is decrease. Aider arc burning, the cathode spots are dispersive and melt is lighter, showing better characteristic of erosion resistant to arc.