| 摘要 |
An ultrasound transducer is constructed to be under damped at higher overtone frequencies by reducing losses through one or more of the following: even pressure shaped surfaces on masses, reversed drive to at least one piezoelectric ceramic, an ultrasonically formed metallic bond between the transducer's front mass and the radiating surface, high current carrying strain relieved electrodes, fine grain structure masses, low internal friction masses and radiating materials, and zero bias stress change due to temperature variations. Improved methods and construction details for bonding the higher overtone frequency transducer to quartz are disclosed and include: front masses with cross-hatched or concentric circle patterns and invar front masses or an invar transition mass that is bonded to the quartz.
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