Title :
Bond integrity of microwave absorbers for CEBAF
Author :
Ananda, A. ; Verma, Y. ; Smith, B.T. ; Johnson, P.H. ; Campisi, I.E. ; Finger, K.E.
Author_Institution :
Coll. of William & Mary, Williamsburg, VA, USA
Abstract :
The Continuous Electron Beam Accelerator Facility (CEBAF) uses superconducting niobium cavities. Specially developed microwave absorbing ceramics are used in the cavities to absorb the higher order mode power. The ceramic absorbers are brazed to copper mounts. The structural integrity and the thermal contact of the braze joints are essential. The ultrasonic reflection signal from the various bonds is evaluated to locate voids and partial braze surfaces. The acoustic wave properties of the four components of the structure are used as input to an ultrasonic transmission line model which is compared to the experimental data. There is good correlation between the ultrasonic reflection data and destructive testing of the bonds
Keywords :
beam handling equipment; brazing; cavity resonators; ceramics; electron accelerators; linear accelerators; superconducting microwave devices; ultrasonic materials testing; voids (solid); CEBAF; Cu mounts; Nb cavities; bond integrity; braze joints; for CEBAF; microwave absorbers; microwave absorbing ceramics; partial braze surfaces; structural integrity; superconducting cavities; thermal contact; ultrasonic reflection signal; ultrasonic transmission line model; voids; Acoustic reflection; Bonding; Ceramics; Copper; Electron accelerators; Electron beams; Niobium; Optical reflection; Superconducting microwave devices; Superconducting transmission lines;
Conference_Titel :
Ultrasonics Symposium, 1992. Proceedings., IEEE 1992
Conference_Location :
Tucson, AZ
Print_ISBN :
0-7803-0562-0
DOI :
10.1109/ULTSYM.1992.275879
