【摘要】 电弧侵蚀对电接触材料的寿命有重要影响,借助高速摄像技术,对AgC5电接触材料的分段过程中的电弧进行观测和分析,并研究了电弧侵蚀后的触头表面形貌.在相同电流条件下,随着电压的升高,电弧寿命变长,稳定阶段更为剧烈.电弧放电过程为多点放电和熔桥现象.经过扫描电镜分析,触头表面有大量电弧使得石墨氧化产生喷溅形成的大量细小富碳金属颗粒,并且基体中石墨参与放电挥发后转变为细小的碳颗粒或絮状物沉积在触头表面.综合分析认为电弧从开始放电初期就导致石墨气化挥发或快速氧化为CO或CO₂气体的行为出现,这些行为可以完全解释触头的显微组织变化特点和规律.所以研究电弧对于碳的作用行为对于AgC系触头的使用寿命有重要关系.更多还原

【Abstract】 Arc erosion has important influence on the service life of electrical contact materials. Arc erosion characteristics of AgC5 electrical contact material are investigated under direct current. The images of AgC5 electrical contact breaking arc light are obtained by a high-speed camera, and the contact surface topography is studied after arc erosion. Under the condition of same current, with the increase of voltage, there arc time and the stability of arc steady burning stage performance is more intense. The arc discharge process is accompanied by a multipoint discharge phenomenon and molten bridge. Through SEM analysis, because arc made of graphite oxidation and splash form, a large number of small carbon-rich metal particles were produced on contact surface, and graphite in the matrix after discharge volatilizes into tiny particles or floccule carbon deposition on the surface contact. It was concluded that arc discharge from the start, early leads to graphite gasification volatile or rapid oxidation of CO and CO₂ gas behavior appear, and these behaviors can fully explain the microstructure changes of the contact characteristics and laws. So the research on the effect relationship of carbon between arc behaviors was important for the service life of the AgC electrical contacts.更多还原