Summary
Alumina ceramics are widely used for vacuum insulation in devices such as a vacuum interrupter. In development and design of a vacuum interrupter, flashover along a surface of solid insulator is one of the problems and it is very important to improve surface flashover characteristics in vacuum. Thus, it is necessary to clarify the surface flashover mechanism on alumina ceramics in vacuum. In this research, in order to investigate the correlation between surface resistivity and surface flashover voltage of alumina ceramics in vacuum, we prepared samples of alumina ceramics deposited two kinds of chromium oxide thickness and measured the surface resistivity and the surface flashover voltages of those samples in vacuum. The sample geometry for measurement of surface flashover was a column of 20mm in diameter and that for measurement of surface resistivity was a plate which is 30mm wide, 30mm long and 5mm high. As a result, the surface resistivity of sample alumina ceramics with and without chromium oxide were 3.0×1010 Ohm/Square and 6.0×1014 Ohm/Square, respectively. Thus chromium oxide coating decreases surface resistivity of alumina ceramics. And the surface flashover voltage of alumina ceramics coated with chromium oxide coating is 1.6 times higher than that without coating. The surface charge was relaxed by the decreasing of surface resistivity.
Additional informations
| Publication type | ISH Collection |
|---|---|
| Reference | ISH2017_424 |
| Publication year | |
| Publisher | ISH |
| File size | 569 KB |
| Pages number | 4 |
| Price for non member | Free |
| Price for member | Free |
Authors
C. TATEYAMA, W. SAKAGUCHI, T. SHIOIRI, J. KONDO
Keywords
