纯石墨和铜-石墨的阴极斑点与截流值研究  

Cathode Spot Movements and Chopping Current of Pure Graphite and Copper-Graphite in Vacuum

作　　者：张程煜[1] 乔生儒[1] 杨志懋[2] 王亚平[2] 

机构地区：[1]西北工业大学超高温结构复合材料国防科技重点实验室,陕西西安710072 [2]西安交通大学,陕西西安710049

出　　处：《稀有金属材料与工程》2009年第3期488-491,共4页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(50702045,50871078);高等学校学科创新引智计划资助(B08040)

摘　　要：研究了纯石墨和铜-石墨材料的阴极斑点的特性及真空电弧截流现象。发现纯石墨的阴极斑点呈现随机运动的特点,斑点的直径小于3μm,阴极斑点每次运动的距离约为阴极斑点的半径。而铜-石墨的阴极斑点的运动与Cu相息息相关,它选择性的发生在Cu相上,阴极斑点的大小取决于Cu相的大小,阴极斑点的运动距离为Cu相之间的距离。同时,铜-石墨的真空电弧截流值1.18A,远远大于纯石墨的截流值,这主要是由于两种材料不同的阴极斑点运动特性引起的。In the paper, the cathode spot movements and chopping current of pure graphite and copper-impregnated metallized graphite （Cu-C） in vacuum were investigated. It can be found that cathode spot movements produce an arc erosion pattern composed of a large number of craters with varying distances between them. The size of the craters is less than 3μm in diameter. This pattern indicates that the cathode spot walk randomly on the surface. Whereas, cathode spots initiated selectively on the Cu phases in Cu-C materials. The diameter of the cathode spots depends on the dimension of the Cu phases and the displacement of a cathode spot moving is equal to the distance between the Cu phases. Meanwhile, the chopping current of Cu-C is 1.18 A, far larger than that of pure graphite. The phenomenon can be explained by the different characteristics of the cathode spot movement.

关 键 词：石墨 铜-石墨 阴极斑点 截流值 真空电弧 

分 类 号：TB303[一般工业技术—材料科学与工程]