纳米晶钨铜合金表面上不寻常的电弧分布及电击穿机理

Unusual Arc Distribution on Surface and Electrical Breakdown Mechanism of Nanocrystalline Tungsten Copper Alloy

摘要:

在真空电炉中利用机械合金化和热压烧结法制备出纳米晶块体钨铜合金。在进行电击穿实验时，电弧在其表面出现了分散现象，明显不同于相应传统材料电弧集中在局部的现象。这是由于纳米材料在电击穿时由于较低的逸出功、大量晶界的存在和纳米尺度的粒子能窄化钨铜界面的势垒而诱发大量电子发射所致。

Abstract:

Nanostructured bulk of W-Cu alloy was prepared by mechanical alloying and hot pressed sintering. The nanostructured W-Cu material shows the characteristic of the spreading electric arcs, and the commercially used W-Cu alloy exhibits the characteristic of the localized arcs during the electric breakdown. The effect of nanostructured W-Cu alloy is caused by a larger number of electrons emitted during the discharge with a low electron work function, and highly conductive grain boundaries and many nano-metre-scale grains could narrow the potential barrier at the tungsten-copper interface.