Spherically shaped active transducer based on proton-irradiated vinylidene fluoride-trifluoroethylene 70/30 mol % copolymer
- Department of Applied Physics, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong (China) and Materials Research Centre, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong (China)
Spherically shaped active transducers using proton-irradiated vinylidene fluoride-trifluoroethylene 70/30 mol % copolymer films as the active elements are described. The copolymer films prepared by hot compression molding were irradiated with a high energy proton over a broad dose range (20-250 Mrad). The electrostrictive and piezoelectric responses of the copolymer have been characterized before subsequent transducer fabrication. The performances of the focused transducers constructed with a 4 mm aperture size and epoxy backing were evaluated under dc bias voltages. The transducers with focal lengths of 17.4-19.0 mm and a center frequency of 19 MHz display a broad bandwidth up to 94%. Besides, the transmitting output of the transducers increases with the dc bias voltage. For the copolymer active element irradiated at a proton dose of 107 Mrad, the transducer shows the highest transmitting voltage response of 1.34 kPa/V.
- OSTI ID:
- 20779379
- Journal Information:
- Review of Scientific Instruments, Vol. 77, Issue 5; Other Information: DOI: 10.1063/1.2200878; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0034-6748
- Country of Publication:
- United States
- Language:
- English
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