Influence of thermal conductivity on the breakdown field of niobium cavities
To experimentally check the predictions of the thermal model for the influence of thermal conductivity on breakdown field levels in Nb cavities, eight elliptical cavities at 8600 MHz have been built from material with RRRs of 25, 50 and 100 (RRR ..cap alpha.. thermal conductivity). After several rf tests on each cavity, the RRRs were increased by outgassing at about 2000 C in a vacuum of about 10/sup -9/ torr using resistive and induction heating furnaces with high pumping speeds. From a total of 40 tests on these cavities with RRRs ranging from 25 to 1400 the breakdown field is found to be roughly proportional to the square root of the RRR. Fabrication methods were kept the same for all the cavities and identical chemical surface preparation procedures were applied to the cavities before and after changing RRRs. * Supported by the National Science Foundation with supplementary support under the U.S. - Japan Agreement.
- Research Organization:
- Laboratory of Nuclear Studies, Cornell University, Ithaca, NY
- OSTI ID:
- 6340192
- Report Number(s):
- CONF-840937-
- Journal Information:
- IEEE Trans. Magn.; (United States), Vol. MAG 21:2; Conference: Applied superconductivity conference, San Diego, CA, USA, 9 Sep 1984
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
GENERAL PHYSICS
36 MATERIALS SCIENCE
NIOBIUM
THERMAL CONDUCTIVITY
SUPERCONDUCTING CAVITY RESONATORS
BREAKDOWN
FABRICATION
GHZ RANGE 01-100
INDUCTION FURNACES
PERFORMANCE TESTING
RADIOWAVE RADIATION
SUPERCONDUCTORS
SURFACE TREATMENTS
TECHNOLOGY TRANSFER
VACUUM STATES
CAVITY RESONATORS
ELECTRIC FURNACES
ELECTROMAGNETIC RADIATION
ELECTRONIC EQUIPMENT
ELEMENTS
EQUIPMENT
FREQUENCY RANGE
FURNACES
GHZ RANGE
METALS
PHYSICAL PROPERTIES
RADIATIONS
RESONATORS
SUPERCONDUCTING DEVICES
TESTING
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENTS
420201* - Engineering- Cryogenic Equipment & Devices
360104 - Metals & Alloys- Physical Properties