Vacuum arc characteristics on nanocrystalline CuCr alloys

Abstract  Vacuum arcs generated on nanocrystalline CuCr 5 alloys were observed by a digital high-speed video camera. Experimental results show that nanosized Cr particles have strong influence on arc characteristics. The arcs are much more stable on nanocrystalline CuCr 5 alloys and the chopping current is about 0.8 A, which is much lower than that on coarse crystalline CuCr 5 alloys. Spots can directionally move a long distance on nanocrystalline CuCr alloy whereas the spot motion is totally random walk on Cr particles for coarse crystalline CuCr alloy.