Surface flashover across ceramic disks in vacuum at cryogenic temperatures

H. Keene, J. Dickens, A. Neuber, H. Krompholz

Research output: Contribution to conferencePaperpeer-review


As superconducting technology becomes more viable in the marketplace, especially in high power applications, the need for a well researched high thermal conductivity electrical insulator is needed. The electrical failure mode for these types of insulators is often surface flashover at sub-atmospheric temperature and pressure. Testing of two such insulators, aluminum nitride and aluminum oxide, for this failure mode is done for two differing electrode geometries. In addition three coats of GE 7031 dielectric varnish are applied to the exposed parts of the insulator for comparison testing with non-varnished samples. In general the testing shows an increasing breakdown voltage trend with decreasing temperature. These results indicate a temperature related dependence of the secondary electron emission and electron induced outgassing, which is a component in the process of surface flashover. The addition of the varnish results in a lowered breakdown voltage. The research also covers the effect of electrode conditioning, and presents optical diagnostics of the gas species involved during breakdown.

Original languageEnglish
Number of pages4
StatePublished - 2003
Event14th IEEE International Pulsed Power Conference - Dallas, TX, United States
Duration: Jun 15 2003Jun 18 2003


Conference14th IEEE International Pulsed Power Conference
Country/TerritoryUnited States
CityDallas, TX


Dive into the research topics of 'Surface flashover across ceramic disks in vacuum at cryogenic temperatures'. Together they form a unique fingerprint.

Cite this