Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
9808685 | Materials Letters | 2005 | 4 Pages |
Abstract
The tracks of cathode spots produced after arcing on the surfaces of nanostructured W alloys were investigated using a scanning electron microscope (SEM). For nanostructured W-2%ThO2 cathodes, the distribution of cathode spots was dispersed and their geometrical properties were completely controlled by the shape and size of ThO2. For nanostructured W-20%Cu cathodes, the spots were also separated on Cu-rich phase. The results showed that cathode spots on the surface of nanostructured W alloys were quite different from those on the surface of commercial W alloys with coarse grain size, and the microstructure of the cathode materials had significant influence on the cathode spots propagation. Also, space-charge regions induced by internal electric field at the interface which responded to the effect of microstructure on cathode spots were suggested.
Related Topics
Physical Sciences and Engineering
Materials Science
Nanotechnology
Authors
Yafeng Su, Wenge Chen, Fazhan Wang, Bingjun Ding,